I think if people are just after a multiplayer-focused RTS that Blizzard is still capable of delivering a top quality experience.
Where I am skeptical is their ability to deliver a top quality single player campaign. SC2's campaign had some of the worst gaming writing I have ever seen — and I've seen a lot of bad writing in games. The missions themselves felt over-designed / QA'd to the point of just being tutorials for individual units.
They can do the multiplayer, I'm confident they could pull that off. I also don't have any interest in that. Can they make the single player experience fun? I'm skeptical, but would like to be proven wrong.
And hey you do you and yeah Diablo 4 seems to have dialed the excessive monetisation back we saw in Immoral. So that's good but it doesn't convince me that Blizzard can actual do something right again. Case in point: Overwatch 2.