Highly abstract and general typeclasses for standard mathematical and algebraic concepts are extremely useful and not eschewed. With them you can do genuinely generic programming in a syntactically convenient way. Examples include: Functor, Applicative, Monad, Num, Floating, Integral, MonadState, MonadReader, Profunctor, Contravariant, ...

Typeclasses which are ad hoc, specific, and typically defined on a per project basis, are much more debatable. If you have the concept of "rendering to the screen" and you have typeclass Renderable with a render method then this is really no better than just writing separate functions for each instance of the Renderable. This isn't genuinely generic programming, it's just symbol overloading.

I wouldn't say they are eschewed.

Haskell programmers do seem to prefer typeclasses that come equipped with some set of meaningful "laws" that help to reject "unreasonable" instances.

And even without that, they are very useful for data type conversions and the like.