I've heard many fans say that they will stop watching tennis when Fed retires: then they are not tennis fans, they are Fed fans, into the personality cult more than into the sport.
Our sport is bigger than any one player... It will be interesting to see what will happen then, the playing field will be more level, we won't have one player getting all the crowd support in all the venues all over the world. It'll be weird...
well yes ... but I can say my experience : I watched tennis a lot in the 80s and in the first half of the 90s then I got disinterested, parly for reasons external to tennis for sure but also because tennis just got less interesting in my eyes (and I know I'm not the only one who lived that). It just didn't have the same variety and excitement it had in the 80s imo.
Then I watched few tournaments from time to time (didn't miss Roland-Garros, the US Open 2002, Masters 2001 I remember all of them clearly) but it was not the same as it had been ... and then I discovered that Federer-guy in Houston 2003, and even not in his first match, in his second one against Nalbandian actually, I think I had never seen him play before, I had not even watched Wimbledon.
And it was a shock : something new and very exciting
And then I watched everyone of his matches and more and more matches, and you know that I've followed a lot a lot of matches in the last years and am interested in all players now, not only Roger ... but the truth is : it's Roger who brought me back to tennis.
Then surely Roger is not tennis but I can understand that in some periods of the game, the game is not so exciting and there are not so many exciting players : I can definitely understand that about the current and probably next period, noit only because of Roger leaving actually, there were many other exciting players in his time with different styles Roger, Gonzo, Haas, Safin, Nalbandian, Ferrero, Hewitt, Roddick, Youzhny, Blake, Davydenko ... just look at the popularity polls
... and for tennis styles also think of Fish, Ljubicic, Rochus, Lopez ... the question may also be raised if in the end Nadal will not be "linked" to that period as well if he declines from now. And surely the young Djokovic is attached to it
the problem is that it's not only Roger who's leaving : it's also all of these styles, it's also the one handed backhand ...
A lot of these players left in last years or will leave soon, and then Fed leaving will not only look like Fed leaving, it will also look like a style of tennis leaving, like an era of players leaving, many many symbols actually, also as he will probably be the last one of that era to leave.
Then I don't think it's as simple as saying "if you leave tennis then it means you're only attached to a star or to a personality". One has to be realistic : most of those will probably still follow tennis but they may do as I did in the second part of the 90s and beginning of the 00s : have lost passion and just watch it from time to time. Even if they don't decide that at the precise moment Fed will retire, it may be the process which may happen in the long term for them (and for some of those this weariness movement about current tennis has already started before Fed leaves actually)