You have just posted a lot of anecdotal data.
No facts.
I have shot bears with rifles, shotguns and handguns.
Handguns have proven very effective against bears in self-defense shootings.
I’m going on the 50-60 videos of bear maulings and survivors
As well as bear hunting vids
I don’t hunt bears
You can use .22 WMR if that suits u
Or a recurve
If I’m camping in big bear country remotely I prefer to be more assured of survival
A look at the rifles professional guides use for brown bears generally starts at the .338 and goes up from there. The .375 Holland and Holland has been relatively standard for many years and the .416s and .458s make up a smaller but significant percentage. One legendary Kodiak guide even used a .500 Nitro Express. But guiding for bears isn’t the same thing as hunting them. Few people shoot a .458 or .375 really well and good shooting tends to eliminate all the drama that a big rifle needs to clean up. While plenty of residents use a .375 for hunting brown bears, a lot more use a .300 or .338 magnum and do just fine. In many cases, it’s the same .300 that they use for everything else so they have a lot of familiarity with it which tilts the balance in their favor.
They have a comments sections you can take it up with them on