35 is still a good age for boxers. If he was Mayweather's age (40) then he would definitely not have much of a chance against an in form Canelo imo.
It depends on the boxer. Most boxers do not age well. Also, the more their success/technique depends on athleticism, the worse they age. Take for example Roy Jones Jr, versus Bernard Hopkins. Hopkins, all about spot on defense and technique via fundamentals. RJJ based on preternatural reflexes and speed. Roy gets old, he get's KTFO'd by everyone and their mother. Hopkins gets old, he finally falls off at like 50.
I'd say GGG isn't exactly a technical lord. If this was heavyweight, I'd say it doesn't matter as much. At heavyweight everyone tends to be slow enough that power remains dominant. At lighter weights, loss of speed can be killer.
So we will see. 35 is getting old for someone like GGG with his style. So we will see.
