Issue is that for domestication to be possible, there has to be a preexisting social structure like herding, colonies, or packs. If it's too weak or non existent, there's no chance that domestication is possible. Having docile examples are always going to be a thing, as snakes aren't exotic pets nor social by any stretch, but that's not what domestication is.

There's an additional risk with omnivorous/carnivorous animals could see people as prey, and this risk pretty much goes up with the size of the animal.

I have no idea how bears act with one another, but I do know they can eat meat and are basically person sized.