Huh.
I think a lot of it comes down to viewpoint. For example, if I was playing a character, and due to some quirk in the rules it became evident that my character was "broken," then I would discuss with the DM how to fix it ("nerf") the character- and I'd be okay with that. And I expect that when I DM, players using 3PP (UA, other materials) do the same.
I do not think that it is, or should be, the DMs job to "compensate" for broken characters by throwing stuff at them. IMO, that just compounds the problem, and becomes an escalating power war. But every table is different, I guess.