I think the thing is, Mel Brooks never wanted to make sequels because he never saw them as interesting (and I'd tend to agree with him). And for the last 30 years or so, he seems like he's been way more interest in musical theater rather than film anyway.
But then content-desperate streaming services started throwing massive amounts of money at literally every available established brand, so when they called him up and asked if they could make sequels to his stuff, he's like "Why the fuck not? I'm in my 90s and don't give no shits no mo'." Especially because he's not actually writing anything new. He's just selling them the name and his acting services and other people are doing the writing (which means the end result is pretty not even remotely a direct successor to the original). He's cashing a check, and Hulu/Amazon/etc are just exploiting his name and rep.
But even beyond all of that, if we're going to be honest, Spaceballs was probably his last great movie. Robin Hood was fun but had its flaws, and Dracula: Dead and Loving It was more flaw than fun (and I'm mostly ignoring Life Stinks because it's so unlike most of his other work). So I'd argue he was already burning out in the 90s. Regardless of how involved he would be with a project today, I don't think we'd ever be able to get another Blazing Saddles, Young Frankenstein, or Spaceballs ever again.
And we sure as fuck aren't getting one in the mid-2020s.
I don't think I've seen the Dracula one. Robin Hood I probably watched but can't remember.