Of course it's a lot harder than building one side and then claiming that the other side sucks because the whole paradigm sucks (but we still wanted some research grants (looking at you, OCaml)).

Scala's OO+FP approach allows me to appreciate both sides where they have their strengths. This is in contrast to languages like Haskell which can declare that FP is the best thing ever (because that's the only way to write programs in Haskell ("but, but, you can do these terrible contortions and write things that look like OOP in Haskell" – let's just skip that point, it doesn't add anything to the debate)).

   it's just the only currently known way where
   both modular and functional sides are actually 
   useful without introducing completely separate
   sub-languages.

   would get a lot more funding 

In case people were wondering, the 1ML project can be found here: https://www.mpi-sws.org/~rossberg/1ml. The key idea here is that ML-style modules (which in the past were though to need a separate module language) can be coded up into System F-omega (the "workhorse of modern compilation").

I don't think any of the 3 main guys behind it (Russo, Dreyer, Rossberg) works on modules all that much right now. That may explain the relatively tardy speed of development.