The main problem for me is the old "fish rots from the head down" effect -- when the rude and entitled behavior comes directly from the top, it's no surprise when everyone else starts acting like that and gets at each other's throats. It should be obvious by now where this weird sense of entitlement and refusal to understand other people's culture is coming from.
>feel free to fork it and start up a parallel project without the problems you see
Most Linux distros are basically already doing this. They all have their own patchsets. It's well beyond correctness and hygiene at this point, if you actually look at the changes that are being disputed, it already falls a lot more in the "cultural differences" category.