They may learn moves past Lv60, but none of them are good enough or necessary that you need to level up to get them. The obvious exception are some uber Pokes (like Lugia that doesn't get Aeroblast until Lv77), but I don't bother using them anyway.
I'd do some research before saying that with such confidence; I lot of pokemon get their best moves late. A prime example is vaporeon- it doesn't learn hydro pump until lv 71. The same goes for suicune, and a handful of others. And what about explosion? Claydol doesn't get it until lv 86. There are more examples, and although a lv 50 pokemon can generally have a desired moveset, there are exceptions. Oh oh here's another good one, relecanth get's Mallet at lv 76. XD