Uh, no. This precludes the possibility of saying "I know this cannot fail (modulo seriously crazy situations like hardware failure or OOM)", which lets you significantly reduce the number of spurious exceptional conditions you need to handle, which reduces code noise if you actually try and treat every impossible exceptional case as if it were possible and increases safety if you don't.

This criticism makes no sense; I don't know what you think monadic computations are, but it isn't what you think. I'd be more specific, but I honestly don't know what you're thinking.

The fact that the posted explanation is wrong doesn't help, I'm sure.

It seems you think all Monads are Maybe, or List?