Essentially, there are three sitations:
a) Everything is of the same difficulty. b) Haskell is more difficult than Ruby. c) Ruby is more difficult than Haskell.
I'd say (b) is a much saner conclusion.
Accordingly, yes, newcomers to Haskell will probably have difficulty understanding what the type system is telling them, and this will slow them down a bit. But analogously, newcomers to Ruby (especially those using a heavyweight framework) will have difficulty figuring out why their application is doing what it is, and this will slow them down a lot.
(Source: I've worked professionally in both languages.)
For ruby still there would be some topics you need to know about before trying to learn language itself, if you are just starting out.
To be fair, that is not an uncommon situation.