I think what they were trying to say is that Tokio ended up being a general purpose async runtime so naturally it can't be the most optimal solution for every c

I think what they were trying to say is that Tokio ended up being a general purpose async runtime so naturally it can't be the most optimal solution for every case. But because various libraries kind of force you into Tokio, it's very hard to use a runtime that's optimal for your specific problem. You'd have to give up on a lot of convenient libraries out there.