Which one of those doesn't invalidate your existing books, because they've been pretty clear all along it's that one.
I feel like this is the "cutting the baby" sort of moment, where you really can't revise the rules without invalidating things. I also feel like that's more the argument for some of us than what it's being called: in trying to keep everything, you end up making it so that improvements might not take in the community because those improvements might be nerfs. It's less about calling it a new edition as much as calling a new edition makes a clear delineation compared to mess of trying to keep it all. I still feel that is where it's eventually going to lead, where it becomes too much hassle design-wise to keep everything together, so they should honestly get ahead of it.
Fine. The 2024 PHB is 6th edition. Please proceed to burn all your 5th edition materials and begin the expansion treadmill again from ground zero. Consume! Consume! Consume!
Happy now?
Why does this have to be so dramatic? We're 10 years into an edition. Bloat happens, built on top of ideas that maybe weren't the best but were the ones they were taking. When things the lawn is starting to get overgrown, adding new flowers isn't the greatest solution.
Like, 10 years for a gaming edition isn't bad at all. In fact, that's pretty damn long compared to, say, tabletop wargaming. If WotC were to actually put out an RCR or whatever, I feel like few would think of it as an "expansion treadmill" because the output rate of these things isn't the same, plus it doesn't really affect the most numerous product: adventures.
Yup. It ultimately comes down to "use what you (and/or your DM) want."
If you like the old one better, use that. If you like the new one, or think it's "better balanced" (which, I mean, we ought to all hope that they'll improve on SOMETHING, right?) or whatever, use the new one.
Most people will probably move on to the newest versions of things (better or not) just to play with the shiny. And that's okay. But I don't think WotC is creating "confusion" by making mixing it possible. They're just acknowledging that IT DOESN'T MATTER that much if things aren't "perfectly" squared. Many of us are just too fussy to agree with that.
See, I feel like the reality is disagreeing with you right now, given how many times Wizards has to say that this isn't an edition change. If even if a small, vocal minority were saying that, I don't think they'd address it. Instead, I think people see a "playtest" and think "new rules". I think they'd be better off leaning into just admitting it's a new edition and saying "Your adventures won't be invalidated by this" because it needs to do less work to actually guide people to where they want.
Also I think more experienced people are way more willing to make jumps, hack things, etc, than newer people to the hobby. In fact,
especially newer people to the hobby. I don't think we should look at that as a good way to on-board GMs because I think most people, when they come into this sort of game, see rules as
rules. It takes time to build up a knowledge of how things work to where you feel comfortable modifying things on the fly without mussing things up. At least, that's been my experience in teaching new GMs over the years. It's easy to feel like you can just jump into this stuff when you've been reading rules for years, but for many it isn't.
And I personally understand (and relate to) that fussiness. For example, I would NEVER have mixed 1e and 2e stuff back in the day, or 3.0 and 3.5 for that matter. I'm quite a bit more easy-going about it now.
5e is so softly (some might say "poorly") balanced in the first place, that nothing is really broken by, for example, giving a 2014 feat for "free" to a background. It's also easy enough for a DM to "fix" even that slight imbalance - by only allowing half-feats (and removing the ASI), using the level one playtest feats only, or frankly just making up (homebrewing) feat-equivalents. All of those options (and presumably more) are "fine", as long as the group is comfortable with them.
Eh, I think there's a point for the game makers to curate things more firmly and then let GMs make their individual choices as they come. I think it's easier to have a strong baseline game and then hash out details rather than potentially picking and choosing between two books.