Wish this was a multiple choice poll.
Editions are controlled by the suits. I don't see them passing by the 50th anniversary without putting out something, so the "no" is right off the table.
What do I think they'll put out? I've got three possibilities.
1. Special 50th editions of the core (and other?) books. Fancy covers, new art, that sort of thing. Maybe some new material, but no changes to existing. You can sit around a table with people with 1st printing (with the errata) and these and not have a single rules debate because something has changed.
2. A "soft partial edition notch up". I think we'll never see a distinct ".5" like 3.5 again - there was a lot of blowback from fans about that. I think we'd more likely see a soft change like Essentials was for 4e. So that you can make a character with the original books and it's 100% (truely 100%) could be made with the 50th Anniversary rules, but those 50th Anniversary rules can also do more - maybe Tasha's ability score changes are baked in, or there are additional subclasses, or they have more variant features for base classes like Tasha's, or whatever.
3. True new edition, 6e. This I think is the least likely with how 5e has been doing and all of the non TTRPG IP coming out that they wouldn't want to rock the boat - again this is a business decision made by suits. But I won't take it off the table. It would be a nice long run, and core book are the most evergreen in keeping up sales.
I'm not sure if I think #1 or #2 is more likely - I think #1 is the least they will do to take business advantage of the anniversary. And if they are also planning movie/games/software/etc around it then it might be enough. A big "Year of D&D" might be a thing.
But WotC, while wildly profitable for Hasbro, has had diversity and social media missteps and may want to push a new more inclusive vision, and that will push towards #2 or #3.