If ifs and buts were pots and pans, there'd be no work for tinkers' hands, Viv lara never had the longevity to last as long, in fact viv was pretty bad in the last couple of years of his career once he lost his hand eye coordination, gooch doesn't even deserve to be mentioned alongside those names. Sangakara did well to retire when he did, we've already seen that once a players loses form due to age it is a very steep fall, guys like ponting and dravid went from averaging 58 in test cricket to retiring with an average of 51, so no, not everyone can last 200 test matches, in fact only one player in the history of the game has lasted 200 games ( and when you add 463 odis to it, it becomes almost impossible to believe that a player can endure such a huge amount of cricket).
Cook can try and play another 50 matches but once he loses his form ( he's already lost his form, he averages 40 in the last 2 years) he is only going to get worse