I know what he's done and I know what he's said. Those aren't opinions. You simply choose to ignore them based on the concept that what anyone did in the past or says in the present is meaningless and we can never know what anyone thinks no matter what or how often they tell us they are thinking...so it's more likely than not the opposite is the case.
Favre played past his best years because he's a selfish, self absorbed individual who always attempte to live life on his terms. Always was that way, and not just on the field. Tom has been the anthesis of that. Warner was a prolific passer when surrounded by exceptional talent and not pressured. When injured or not surrounded by exceptional talent or pressured he was a mistake waiting to happen not to mention a sitting duck waiting to be injured. He was fortunate that AZ drafted Lienart. He's not the brightest bulb on the planet, and he's never been terribly accountable on the field. Brady is his anthesis, too. But Warner was smart enough or the concussions scared him enough to know it was time to quit while he was still ahead, barely.
Bill and Tom have a lot in common. Both are perfectionists addicted to a game, still performing at the top of theirs and still enjoying the hell out of the whole process right down to the minutae. Players and coaches leave because they burn out mentally or wear out physically or both or become complacent and disinterested in the minutae and start to rest on their laurels often wearing out their welcome in the process. I'd be interested to see what signs of anything like that you see emerging in Tom or Bill's case, because frankly I don't see any in either.
Now, health or injury concerns can appear out of nowhere and derail anyone's clear intentions. Whether they're 60 or 34 or 22... But barring either of those befalling either of them, I don't see any rationale for opining that they will probably or likely be done here any time soon beyond projecting your own feelings (I've done enough, made enough, want to try something else or just enjoy the fruits of my labors) onto guys who obviously aren't wired that way. Believe me, show me the money and I'd retire happily in a heartbeat. But then I've never had a career that fascinated me.
Bill likes to fish and golf a little and spend time with his kids often related to sports and coaching. Tommy likes to golf and surf a little and travel and spend quality time with his supermodel wife and the boys. Neither of them appear to be in any rush to do any or all of those things full time. Brady has repeatedly stated (especially since missing the 2008 season) that he can't imagine what would ever replace football in his life. He hopes and intends to play to or into his 40's. He knows some day something will have to replace football, but he has no clue what that could be. Nothing has in Bill's life for 38 years now. Ergo I think they will both do what they do for as long as they can do it on an acceptably high level, and then they will move on and figure out if there is something else to replace it or if it finally just ran it's course. And neither one will hang around when the time has come because they aren't self absorbed jackasses or opportunists in it for the money.