I'm not sure if the size is related or not. It could be.
Personally I find that most programmers/programming enthusiasts tend to be quite friendly in general. (Not all, but most.)
However, I think the most important thing is that people come here because they want to be helpful and make the Pokitto even greater than it is.
In a lot of places on the internet, people pick a fake name and say mean things because they think they are 'anonymous' and can't be caught/found out.
But here people want their contributions to be linked to their name, so naturally they behave nicely.
(Hopefully, like they would in the real world.)
If people here were mean then nobody would visit and nothing would get done. We wouldn't have any cool games or neat programming libraries.
(That's my view/opinion at least.)