Unless a project starts nobody can work on it.
Unless we start using OOP in SMF it's very unlikely that developers with good knowledges of OOP would be (deeply) attracted by it.
Use OOP on the current code base could be not the easiest thing to do and probably not even the most attractive (it's mostly a rewrite of the entire code, you can take it piece by piece, but in the end means rewrite it).
The development of smCore and 3.0 will be for sure more open in respect to what SMF's development has been in the past, so many more people will be able to join and demonstrate their skills.
As far as I remember it's also easier to improve code in an OOP code base rather than in a procedural one.
So I understand your fears, they are absolutely legitimate, but I also think that break legacy and move forward is also something that must be done at a certain point.
Without a lot of new programmer with a very good know how in OOP and all other, this project is dead before starts. My 2 cent...
When the coffin is ready let me know I'll go buy the nails!