I suspect one aspect is a sort of "generational gap". In the 2010's a lot of new languages were created by younger people who wanted to put their own language o

I suspect one aspect is a sort of "generational gap". In the 2010's a lot of new languages were created by younger people who wanted to put their own language on the tracks: NiM, Zig, Odin, to name a few. Similarly, a second aspect is that other new languages raised, but not in the "cool- kid" category, this time rather in the "big-company-backed" one: Go, Rust. In both case : more concurrency, less seats. To season the salad you can add a few errors in the leadership, too much time to create a real organization, the missing "killer-app" too ?, etc.