I'm sorry, but, the hyperbole here is just breathtaking.
I don't know about anyone else, but, of all the people I gamed with over the years, and it's been quite a few over the past 20 years, I can count on one hand the number who bought or used 3rd party products. The overwhelming majority of gamers doesn't know about and doesn't care about the OGL.
I say this as someone who HAS been a supporter of 3rd party products since day 1. My first 3e campaign was set in Scarred Lands. I ran the World's Largest Dungeon. I own multiple Kobold monster manuals for 5e and have run more than a few 3rd party modules. Hell, I've had published 3rd party producers at my table. Yet, any time I've suggested using 3rd party products for anything - classes, spells, races, ship combat rules - anything, I've been met with nothing but crickets. If it doesn't have the WotC Brand of Approval on it, it doesn't exist.
So, no, this isn't the "end of D&D".
Which doesn't mean that it's not important and something we should be talking about. Sure. Absolutely. I strongly disagree with what WotC has done and I hope that cooler heads will prevail ultimately and most of this is going to go away. Again, as I write this, NOTHING has been decided. Nothing is set in stone. Yes, WotC wanted to do stuff that is mind bogglingly stupid. But, they haven't actually done it yet.
Until such time as there is an ACTUAL OGL 2.0, not just a draft document, but, the actual thing that is official, I'm going to reserve a lot of judgement. And I certainly won't judge anyone else for either leaving D&D or staying with it. Either way is perfectly fine. Because, there's one thing about, the louder and more hysterical people keep getting, the less likely I am to actually have any sympathy for the position.