The only people who possibly answer that with any degree of accuracy are the fringe panelists of the great 1970's team. I know panels were smaller back than, so we are not comparing like with like. Back then, just to be on the panel, meant that you were probably in with a decent shout to get a game. It's not the case now.
But only they can say with any degree of accuracy, was it worth it at the time, to be a bench jockey on a legendary Dubs team, instead of going off and doing something else....be it hurling or soccer or whatever. We, on the outside looking in can only speculate on their motivations.
Given that the hurlers have not been able to replicate the success of 2011 and 2013, I know what my opinion is. If the hurlers were in a better place, we probably wouldn't even be having this conversation, as Brady would have stayed put where he was.
Bryan Cullen and Alan Brogan played little to no role in our 2013 AI win. Mossy Quinn played a limited role in 2011. Did they feel a genuine part of the panel then, or did they feel like they were just hangers on? Given how much talk there is of the importance of A vs B games and behind the scenes leadership of non starting regulars, I wouldn't be too quick to discount the over all importance of panel members who don't get the headlines on match day.