We're getting into this argument again are we?
I'll never understand why people hold so tightly to the .5 moniker. The part that's oddest to me is how they've managed to convince themselves that it's some kind of objective truth. Fell for a marketing gimmick from 20 years ago, did you? I mean, go ahead and call it 5.5 if you really must, I guess - but it's not objectively a good name.
(Personally, I think it's a terrible name, just as I think that 3.5 was a terrible name 20 years ago).
We don't actually need to even keep the 5e. The 2014 books weren't really the 5th Edition of D&D, after all. WotC tried to get off the edition bandwagon, but they didn't manage to pull it off that time.
It's D&D24. No need for a decimal.