Why are the refs not calling this BS. If NFL really cared about late and unr hits, they would put a ref in the booth or a call from NY to start calling these penalties. These fines mean nothing to the players. Suspend them for a game, take away a game check, make the team suffer. Then it will stop.
Allen could have easily gotten concussed on the late hit.
https://operations.nfl.com/inside-football-ops/rules-enforcement/gameday-accountability/