Disagree legacy is overall consensus. Nixon to some was a great President who got a lot done. Kennedy to some was all style and no substance who never accomplished anything substantial. However we know what there legacies are and how history generally perceives them.
Whether we like it or not, Spygate is one of the main things the public at large thinks about him. It's unfortunately something he's going to be remembered for. When he goes into the HOF alot of people are still going to bring that up. I think it's the biggest non story ever, but it took on it's own life. It was bs. But it's honestly not going to be remembered as a non story, as much as we know it is.
Someday I'll be dead and you'll be dead and people will talk about Belichick in the same terms we talk about Lombardi who for the most part we didn't watch. And that will unfortunately be part of what those people talk about. Will it supersede him being viewed as the greatest or at least one of the greatest coaches ever? Probably not. But it will be caveat added on. In a sense I think Brady did far more good for himself dragging deflategate out into absurdity because it wore so many people down that it became a bit of a joke and even people who hated us were so sick of it they began to laugh it off as something that the NFL pushed too hard on. 99% of the issue with Spygate was how Goodell handled it all shady. It just sucks we were on the receiving end of it.
This is another thing that people are going to have a very hard time letting go of and I think for a long time it's going to be the story of how the greatest coach ever exercised his control a step to far and probably hurt the team overall.
Without a really good reason, it's always going to be hard to justify the head coach benching a player he felt should start the most defensive snaps all season on a top 5 defense and never playing him while his defense got torn apart in the Super Bowl wasting and all time performance from the greatest QB ever. It's going to stick and honestly, without a really compelling reason, it's going to be hard to give Belichick much leeway on not only not starting him, but not going back to what worked all season.