I wouldn't read too much into that. The Friends salary thing is pretty much unique and shouldn't be a benchmark on how close a cast is.
A much better gauge for me would be to watch the gag/blooper reels for each show.. when people mess up or goof around you can really see how comfortable they are with each other and having seen them all for each show (yeah.. i love bloopers reels
) i can say that each cast seems pretty much comfortable and close with each other (and HYMIM is far more racy at times
As a contrast watch the gag reels for Community.. especially the ones from the later seasons and see how they react to Chevy Chase. You can feel that the others are not really including him in their antics that much and try to keep a distance.. anyone who's familiar with the background workings of the show knows why that may be the case.
It does matter. For the Friends 6 main cast members to collectively bargain for equal pay does show how close they were. You don't see that from the cast of HIMYM even after 8 seasons and especially after Jason Segel intending to leave after this season.
The gag reels of Friends do show how close they were, and they even closer than the cast of HIMYM. They were close as a family.