Honestly, they are useful in practice, as long as you’re using a language that supports them properly (I’m not convinced TS is that language). Even without, the

Honestly, they are useful in practice, as long as you’re using a language that supports them properly (I’m not convinced TS is that language). Even without, they constitute a pattern that is very simple to implement which is very powerful. People believed (and some still do believe) the same thing about generics.