The biggest point to this IMO is that it seems Diggs wants to be here.
Every WR FA Possibility since BB left, Aiyuk, Higgins, Kupp, Metcalf, Ridley, who they might have had a chance at, did not want to be here, even for money.
Diggs get Buffalo twice a year, is clear #1 if healthy, has the next possibly great QB throwing to him, plus goes back to his glory days of the AFC East for one more chance.
Few FAs wanted to be here. That culture is already changing plus Diggs has a big mouth. I don't see any situation where Diggs takes the money and doesn't give it his all.
This could become a Washington type destination with any success, even if it takes him a year to be his best.