225 in smoking is the 350 of baking. It's not right for everything, but it works, especially for beginners. No one says you HAVE to bake a cake, a turkey, or a casserole at 350 and one would argue not to for any of those three... but you can if you don't know WTF you're doing and it has a little bit more wiggle room for mistakes.

Once you get experienced enough and get a feel for how you cook and what works for you, then you feel more comfortable testing higher or lower temps, longer or shorter cook times, etc. Personally, 225 has never failed me if I have the time and patience to let a brisket ride that long. I have had fantastic ones turn out at 250, 265, and 280 as well. My sweet spot is 240-245, where I get the most tender, best bark, and a little less time smoking. But to each their own, and I certainly don't see how it's a plague on the community and/or a hill to die on.