Definitely some of those games would have come out anyway -- Kelsey Dionne was working on Shadowdark before the OGL mess happened, although I admit that I mostly ignored it when buying her excellent 5E adventures off her site. But the crisis was definitely a moment where I think a large plurality of D&D players were incentivized to look at what else was available (both Pathfinder and Dungeon Crawl Classics had to scramble to keep up with demand, for instance).
I agree that things are healthier overall in the RPG hobby than they probably have ever been. This probably makes one faction inside Hasbro unhappy, who want the market to be 100% them, but the other folks inside -- the folks who appear to have won the internal battle -- are probably delighted.
Leaving aside DDB, I think WotC will also benefit from more designers trying more things in the RPG space, because ultimately -- as we've recently seen -- they're going to scoop up a cohort of those designers to do stuff for them in future. So even people who don't care about anything other than D&D-branded RPGs will benefit from the third party stuff in the long run. (This is an old phenomenon, of course, especially in the 21st century. Recent events just accelerated the process and expanded the number of designers out there.)