Do you play Magic: the Gathering? Are you aware of the changes they've been making? The increased schedule release?3.5 leading to Pathfinder within 5 years was a failure state. WotC has gone over the reasons they won't do a "5.5" many times, but it boils down to it being bad business to do so. Hasbro wouldn't want them to do that, because of the bottom line. If corporate mandates anything at this point, it will be Edition conservativism because it has been what works so far.
These new options aren't unbalanced with what came before. A handful of variants for each Class and some retraining rules a new edition do not make.
Hasbro only cares for it's bottom line.
I don't know how you claim 3.5 was a failure? In my stores it sold for years as D&D and then for years as Pathfinder 1. And you seem to be overlooking 4.5.
My advice is to look at what's been happening with M:tG.
Magic item changes and some class changes was the major focus of 3.5, IMO they are the basics for an edition change especially if we keep getting more UA updates every week.