I'm probably going to regret asking this, and if the answer is obvious I apologize for not following all 22+ pages of this thread very closely, but:
Which styles are you referring to?
Low-magic is a big one. It's rather difficult to play a low-magic game in 5e, much moreso than multiple prior editions. The 4e style is another. Serious survival, where merely getting one day to the next is a struggle with a dangerous environment, is quite hard unless you go through and rip out quite a bit of stuff (or ban many classes) and port in new rules.
There are also styles, or elements thereof, that have, shall we say, rather
thin support. Heavy logistics play (the other main component of old-school style, after survivalism and low-magic) is pretty sparsely supported, and anything involving politics/domain management is likewise barebones to nonexistent. Exploration, as a recent thread noted, is pretty disappointing. But "little support or all too often no support" is rather better than having to
fight the system to get what you want.
Note that I am of course not considering 3PP in this. Because if you allow 3PP, then every edition has equally supported everything, namely, perfectly, because
someone can write up 3PP rules for anything.