i was going to question your 5% number... but then I remember that you constantly remind us on here that you disliked 4e, and I assume you do IRL too, so you may not be the safest person to talk to about it.... it reminds me of political things I can't bring up specifics about, but there are lots of topics that people being anti can make those that are that way not want to talk about it...
either way even if we assume 5% is correct, the influx of NEW gamers since 2014 means that there are alot of new player that might want more 4eisms
I think there's a lot of room to argue that there are two factors in play for altering 4e's legacy.
On the one hand, 4e was obviously really controversial, and the rise of Pathfinder galvanized the controversy. Now, with more than a decade since the last 4e book, it's far in the mirror, as you say. The hobby has grown a ton, and many of the folks who were brought in know nothing of 4e...and seeing that, even if there were huge (and IMO deleterious...) changes, 5e kept some 4e mechanics. A bunch of people can look on it now with no preconceptions and no prejudice, and ask about what it did well and what it didn't do well.
On the other hand, being perfectly frank, I don't think Mike Mearls ever actually liked 4e. In fact, I think he was opposed to several of its design conceits, and that his (undoubtedly well-meaning) efforts to defy them dealt significant damage to it. The fact that he was the one who cracked an edition-war-rhetoric joke was pretty telling. But with the changes of staffing at WotC, I don't think we have that
internal partisanship anymore. I think Crawford and others are much more willing to go wherever
useful design leads, rather than what seemed like being rather precious with particular things (e.g. Mearls
loves rolling fistfuls of dice, so a bunch of stuff was ultra dice-heavy when it didn't need to be in the playtest, wasting months of effort.)
So I think, both externally and internally, the next decade is going to be kinder to 4e. I had, personally, expected it to be the Forgotten Edition, and we saw
plenty of signs of that years ago. People celebrating 5e developing something brand-new that was developed or refined in 4e instead was...a really common occurrence for several years. Now, though? I dunno. We may see 4e rehabilitated.
I don't think 4e will have too much influence on "5.50" or whatever we come to call 2024 D&D, unless they make the shocking decision to include an actual Warlord class (and I don't think they will, don't get me wrong.) But further down the road? I could actually see a future where 6e (or 7e, or whatever the thing that comes after 2024 D&D gets called) is more of a synthesis of 4e and 5e, something with similarities to 13th Age.