Probably only because their channel had Right Wing in the name. Their automated filter systems commonly do stupid things like that - they’ve banned educational channels for having “Children” in the channel name, for example, in the name of banning underage pr0n.
Their appeal was rejected as well, which means this was intentional.
I suspect that Youtube is aiming to rid itself of anything that’s remotely controversial. They’d rather have a simple, safe little space free from anything that might endanger advertiser money flowing in and they feel as though they have plenty of content to remove everything that anyone anywhere might find slightly objectionable.
Personally, I think that’s a road to a very bland, unengaging platform. But that’s their call to make.