I'm not really seeing what the Steeler player did wrong here. It is a vicious hit but it seems to me that it ought to be within the rules and spirit of the game. I did not know that kickers and punters are ruled "defenseless" throughout the play. That doesn't make a whole lot of sense.

Here the punter is clearly trying to stop the Steeler kick returner from scoring so another Steeler player stops him. whistle That's what he's supposed to do. If he lets that punter make the play, I think the coaches would let him hear about it during film session and being a rookie, he might not have a job the following week. I'm all for player safety but I don't think any one position ought to be safer than any other. If you step on the field and are part of the action, you're liable to get hit. It's a vicious brutal game but I thought this was a clean hit.

"When the snows fall and the white winds blow, the lone wolf dies but the pack survives."
Winter is Coming

Now this is the Law of the Jungle—as old and as true as the sky; And the wolf that shall keep it may prosper, but the wolf that shall break it must die.
As the creeper that girdles the tree-trunk, the Law runneth forward and back; For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack.