Russian mob is one of the most dangerous in the world. My grandfather lived there for 30 years. Told me some very NSFW information about them.
Cheering against a player on the field is normal. Especially if they are great. The enemy. Want them to feel the agony of defeat. But sans being a Tyreek or Hardy individual, that is where the hate should end imo. I don't think it should get personal to the point of wishing injury or what not. Many here probably dislike playing against Josh Allen. Cheer against him. I doubt most would be happy if he tore an ACL in a game against the Pats though.
These guys are all in the same boat. They put their bodies on the line every week for our entertainment. We don't get to experience what NFL players guy through Monday morning. Especially QB's who get beat up pretty good. I can't imagine the pain.
I certainly understand fans are passionate though. NFL has the biggest fan base in the world. With Hockey, most fans follow just their team. In NFL, most watch other games too.
Jmo.