Can you say all other players in the team "try hard"?
Seyfarth gives you consistency and reliability. He's there for every kick chase, he gets behind the ball before any forward and also keeps himself in the frame to give options.
He is the guy the coach shows tapes of to Pole, To'a, Fainu etc to show them what they should be doing.
Seyfarth doesn't win contact for sure, but neither do guys like Cotter, McCinnes, Finucane etc. They just keep their legs moving and show up just in case.
If every player does what Seyfarth did, then Alex wouldn't be in this team.