In production Haskell you need to combine monads using e.g. monad transformers and this is significantly more complicated than just understanding how bind works. It also requires a lot of boilerplate code and any errors there are not obvious to track down.
Writing your own monad transformers is more complicated than understanding bind. Using standard ones isn't: swap out `State s a` for `MonadState s m => m a` (or whatever the relevant effects are) and put `lift` where the compiler tells you to, and you're 90% of the way there.
The other 10% is stacking the appropriate sequence of `FooBarT (BarBazT ... )` at the entry point to your program, which is admittedly pretty tedious.
Alternatively, you can have just a few people that understand how to compose Monads and many others writing code within them.
I'm not sure if I think it's a best practice by any means, but it's a pattern I've seen that avoids having to include monad transformers in onboarding.
