I still haven't seen or heard any evidence that non-fatal shots from under-powered handguns will just anger a bear and make it attack even more fiercely. There are a bunch of videos on youtube where the mere sound of a shot sent bears (including sow brown bear with three cubs) running away at high speeds. A year ago, one guy shot a brown bear in AK with several .45 ACP shots. The brown bear ran away and died. I think the myth that [fill-in the blank] caliber handgun will just piss a bear off when it is attacking come from a bear's response, not to being shot while attacking, but to being pursued while hiding after being shot. When a bear is hiding after being wounded, they do tend to attack a persistent pursuer. I successfully hunted brown bear last fall in SW AK, and I spent a lot of time on the AOD forum. And no one could identify a single situation where a bear acted aggressively after being shot with a low-powered handgun. I think it's a myth. I carried a .454 with 360gr HC bullts when I was fishing during the ten-day hunt (got the bear on the first day, so there was a lot of that), and a big bore magnum obviously will better incapcitate an bear that already has decided to make an aggressive, unstoppable charge on the person. But, I think it's a myth that getting shot with a .40S&W or 10mm will just make a bear more angry. It appears to me that, when even a massive brown bear gets hit by moderate handgun cartridge, they feel a lot of pain and shock (partly because of the noise) and usually go away. Now, they probably will attack you if you pursue them after shooting them. But i has seen nothing to actually suggest that even a large a bear being pelted by something like 180gr bullets at 1,200 fps (something like a .40 S&W) will increase it aggressiveness toward the shooter.
There, of course, is the seperate issue about whether or not this leaves others more vulnerable to a wounded bear later on. But I think that is more of a short term issue than a long term one. I cannot find anyone who can substantiate with any facts the myth that a bear who was injured months or years earlier (not a bear who was just injured and is fighting for its life while bleeding) will be more aggressive to humans because he was injured in the past. In fact, there is strong evidence that bears (like many other animals) are much more shy of humans in areas where they are hunted, than they are in some National Parks or semi-urban areas where they are not. I don't know what the answer is, but it makes more sense that a bear who has been shot by a human in the past, will still clear of them in the future.
As to bear spray, what do you do when the bear is is on the outside coming into your tent to get you? Spray the inside of your tent? I've read several news accounts over the years where a person is atacked in their tent and has killed the attacking bear or caused it to flee by shooting it from inside the tent. Can't do that with spray.