My opinion? He is the boss but not in the sense that he is all that involved. I think most of the work is delegated to his son. Sure he may have final say. But he isn't looking at free agent lists, he isn't deciding who to sign. Take the Randy Gregory situation for example. He was totally out of the loop on that thing, stepped in and then delegated the work to some dude who then blew the deal over a clause in the contract.
So is Jerry the GM? I don't think he is in the sense of what most NFL teams GM's actually do under their job description. He is the GM in the sense that he has final say on everything. But isn't that true of all owners? Jerry isn't out there watching film of college or pro players. He isn't putting in 99% of the work that a real GM does. Most of that is being done by Stephen and to some extent Will McClay. But Jerry is still going to sit in the room for an interview with a coach. He is still going to give thumbs up or thumbs down to an extension.
For the most part Jerry is off riding his yacht and getting drunk at games.
I think he's way more involved than you are hinting at here.
I think it's more than just final "say", it's mostly final "decision".
Meaning he's not just rubber stamping what other people are doing; other people are coming to him (and Stephen) and say, I think we should do X, and Jerry (or sometimes Stephen) makes the decision of whether we do it or not. And if there are multiple choices presented by multiple people, Jerry chooses.
This is not what other owners do.
No, he's not watching game film or researching other rosters or brainstorming how to maximize cap space or those types of things, he leaves that to other people. But those other people present their findings to him and the decisions are (mostly) in his lap.
And yes, Stephen has a very, very big say and I do believe has some level of autonomy on lesser decisions and even on overall strategy.
But I think if Jerry wants to do X and Stephen wants to do Y, X gets done unless Stephen does a very good job of convincing Jerry to switch to Y.
Stephen has a lot of power and influence, and Jerry has ultimate power and the vitriol fans feel should be directed at both.
I think what we are seeing right now and have been seeing for years now is Stephen's plan. But it's only happening because Jerry agrees with it.