Here's how I've internalized stories like this over the years, and applied it to my daily life moving forward:

Context:
I do not drink and drive. I don't go to bars, I don't order drinks at restaurants if I'm going to be driving home, and I don't drink at a friend or family members house if I'm going to be driving home. I don't even keep alcohol in my own house anymore these days (unless I need a bottle of wine for a recipe or something), so if I get good and tanked - it's going to be on a camping trip or something along those lines. I'll have slept it off long before I got behind the wheel.

I don't smoke weed, and I'm not on any medications - prescribed or otherwise.

If I am ever suspected of DUI at some point in the future, the officer making that determination will be, 100%, unequivocally...wrong about it. I will be stone cold sober.

Actionable:
There is no way in which performing field sobriety tests, while stone cold sober and being observed by somebody who strongly suspects I'm not sober, will make me appear any less sober than I already am. There exists a possibility, however remote, that the officer performing the tests will observe some minor detail that confirms what he already suspected anyway. Again - he will be doing this, while investigating a completely sober person. So I'm not going to do them. In effect, he suspects that I'm impaired, and he's asking me to provide him additional evidence of that. I will politely decline, thank you.

At this point, I will probably be arrested for DUI anyway. I might not be (which would be great), but I'd expect to be. I won't be happy about it, but I can't make him not do that if he really wants to. I will be driven to the station, and I will be given an opportunity to blow after I get there. I will absolutely do that, and it will absolutely show 0.00%. There is no chance of me voluntarily agreeing to a blood draw, but if a warrant for one magically presents itself (I can't imagine how or why, but whatever) I will readily comply. And it will come back just fine.

General Thoughts:
If the above ever happens to me (it never has), it will be a massive inconvenience and it may even require me to spend money I really don't have on an attorney. It will be embarrassing. It may affect my job. I will not be happy about any of this, but I also cannot do anything to 100% guarantee that the above never happens. But I can control how I react to it, and how much I even think about it (which is virtually never). My anxiety level over this stuff is therefore...non-existent. I already know what I'm going to do, and not going to do, in the unlikely event it ever happens. It's a solved problem from my perspective, and it requires no additional thought or handwringing on my part.

For the rest of you - you do you, boo.

@gitarmac the "purpose" is obviously maximum flexibility for subjective bullshit to build probable cause, combined with bureaucratic gov't responses of "policy" over: "the one guy that sued & won" or, "the one guy the officer let go, and he rammed a school bus, incinerating 20 kids..." And then, on top of THAT,  decades & generations of "how it's done" all designed to "rattle" ner-do-well types into giving away or betraying information or more PC that would not be admissible in court if they hadn't given it up "voluntarily." Regardless of if they're an "actual" ner-do-well, someone automatically deemed as "ner-do-well" due to the prevailing biases of the time & place. Or, just a harmless 100% law-abiding citizen that's nervous & frightened "just because."

And right there, you have three rather different needs, causes, or motives all informing how the "State's interest in Law Enforcement" is carried out, that are possibly contradictory or even mutually exclusive.

"Your eyes look glassy."

"Well, gee officer, it would be awfully uncomfortable if they had a dry matte or satin finish, don't you think? Do you have a department issued state-approved glassy eye chart, or meter? Like the little window-tint thingy?"

So... what happens next? Did you sarcastically convey Obi-Wan Kenobi-style: "This isn't the drunk or hoodrat you're looking for..." And that's the end of it?

Or, did you just commit: "Misdemeanor disrespect of Law Enforcement in the 3rd degree, with weeks of Process as Punishment. And no charges or fines. So the system works."

Tough call.

And, "Economic Incentives/Disincentives are followed always." Holds very true here too. And "Economic Incentives/Disincentives" doesn't always mean "money" but, performance reviews etc. and ones paycheck ultimately means a lot does too.

And whatever a LEA or government incentivizes or disincentivizes, they and the public will get more or less of "that." Or, any and all unintended consequences of "that" too.

Then, add on top of it how the states respond legislatively to 5th Amendment self-incrimination problems. And they create the Kafka-trap Catch-22 "refusal to breathalyze/field sobriety test" under the doctrine of "implied consent." Which you created by obtaining a driver's license, and if you refuse the "last chance" blood/breath testing at the station, or special mobile van.

And, while it's not a "criminal offense," you are then automatically slapped with all the administrative or civil-forfeiture penalties, as if you actually had blown or had a blood draw of .08%+ BAC.  Assuming there's no additional "Process as Punishment" factors, intentional or not, like some horrid lab backup. Meaning you might wait even longer than actual drunks to get your "work temps" and breathalyzer interlock on your car.

Which... might make someone wonder if the whole thing is really about "public safety," or just the mechanics of State, intentionally or just organically,  "circling the wagons" to jealously defend it's authority, whenever American first principles & the Constitution might threaten it.

And there's interesting stuff like this on the "unintended consequences" front as well. Certain demographics have learned that because of "Implied Consent" it's simply better to never have a state issued Driver's License, so... they just never consented. Isn't that cool?

And, if the State originally screwed the pooch on various reckless driving laws, and oversights like how, at least in Wisconsin, multiple counts of operation on public roads w/o a license don't increase... but operation on a suspended/revoked license does increase...

And you're a participant in the new subcultures of: "Speed limits & traffic signals are uncool, and are for suckas & whites..." Going 95mph+ down Milwaukee streets in whatever un-titled no-plate jalopy you bought on FB Marketplace for $500, or a stolen 202X KIA with inexplicable 1970s anti-theft technology... is pretty easy.

And legally, and just pragmatically, you're at least partially, if not nearly untouchable. The odds Sir Isaac Newton gives you the ol' F=MxA death penalty, are wayyy higher than you'll do even 72 hours in the MKE County lockup.

I paid full price for every key on this keyboard and by God, I'm going to use all of them.

You get more of what you measure out of your employees. This is true in every profession. Law enforcement isn't special, or immune.

Pick your metrics wisely.