5e is not a perfect system, but the more questionable aspects generally seem to serve the causes of accessibility, bounded accuracy, or evoking (if not quite honoring) D&D traditions, all goals I believe in to various degrees, so even a lot of dumb rules are dumb rules I can at least respect the goals behind. 5.5 has yet to find a coherent goal that I can see, certainly none I support, and hence I just have very little respect for the efforts I've seen.
I don't see clear goals with OneD&D beyond change for the sake of making people buy new books. I think 5e D&D is currently in a messy, unsettled state so there is a legitimate basis for a revised PHB to codify the existing tweaks of Tasha's, etc. into the core rulebook, and I wholeheartedly support that (even if I don't love every tweak). But WotC's playtest ideas beyond the changes already semi-implemented to 5e seem aimless and random. All they add up to is "minimum amount of change to make playing at a 5.5 table with a 5e PHB unteniable."
I'm not setting out to be upset. I want to support WotC. But they've given me no reason to. So far they have just asked me to try new things with no convincing explanation of why they are better. I am not so set in my ways as to be opposed to new things because they are new. But so far the pitch I have felt (fairly or otherwise) for supporting OneD&D is "here's a bunch of stuff we're changing for no particular reason; accept it or struggle to find new D&D groups come 2024." That's a threat, not a sale's pitch.
Also, while I appreciate that they have to shill for the brand, WotC's absolute conviction that an edition they haven't figured out the actual rules of yet is definitely going to be better than the wildly popular current edition that it is based on, (which is nonetheless perfectly good enough until 2024) just makes them seem more untrustworthy to me. 5.5 seems like a New Coke debacle in the offing.
So yeah, at the moment, this is probably the edition change where I get off the bandwagon. There's still plenty of time to convince me otherwise, but it will require a serious righting of course to... well... have an actual course I understand and support.