It pains me to see a lot of creative folks in my sphere still using Substack, but I think Substack has been wildly successful getting folks back into blogging by building it primarily around email instead of RSS. Content-wise there's no meaningful difference between a blog and a newsletter, and an online archive of newsletters can still leverage all the features of a classic weblog. To me, this is still blogging even if the organizing principle has changed.
I'm happy to see Ghost, Beehiv, and Buttondown jump into the arena with similar approaches and maybe stronger moral fiber (I guess we'll see).
Blogging was never going to "return" so long as we had to explain RSS and feed readers. That's a solved problem now. Now we need more people blogging instead of heading straight for the next big social media silo.