As a Chiefs fan, I get the frustration with both roughing calls yesterday. I don't think either *should* be penalties, but with the way the NFL is played nowadays both plays are almost always called regardless of the QB. Both plays had helmet to helmet contact on the QB.
The whole late slide issue has been a conversation throughout the league all season, and I'm guessing the competition committee will tweak that rule in the off-season. I think in general more well known players likely get the benefit of a few more calls in comparison to a rookie or lesser known player, but don't see it as specific to Mahomes or the Chiefs. The Chiefs just happen to be under the biggest spotlight right now, and there's a lot of reasons for people to hate them (Mahomes/Kelce are annoying, they keep winning ugly, Taylor Swift, etc).