THEY DON'T.
My dude, Boomer and Gen X players are a fraction of the players they picked up in the 5E era. They are absolutely not going to trot out a bunch of super-expensive books that might get a few old fogies to buy their books again. It would be a wildly irresponsible move, and they save that for not making starter sets connected to Honor Among Thieves.
All the people who buy all the regular 5E books. The Easley cover is going to be the alternate cover and the main book is going to get a standard 5E cover.
Dude, no. Polygon's not great, but they label when they have paid content, as does Rascal.
Everything you've read has been a bunch of people whipping themselves into a frenzy over their collective imaginings. Just wait until WotC actually says more than three sentences about this.
If they bought be a jet and gave me a pet unicorn, I'd be super-excited about that, but it's not going to happen. That's not how corporations work, especially since they already have most of the customers that D&D has ever had.
The fact that some older fans have their feelings hurt that WotC is focused on customers their grandkids' age doesn't somehow mean there's a giant untapped market where WotC is thinking "gosh, if we don't get a bunch of retirees buying our books, we might as well go out of business."