Objective based PVP does (or did) exist in SWTOR- was a few years since I played it - one of the best examples that I can think of was Huttball, in which the team had to move a ball over to the other team"s side and score points i.e. CTF. However roles were not irrelevant at all. I played a sage in that , and as that class could rescue players it had one of the best skills for the match.

Even so, Huttball was a lot of fun in combining PVP with teamwork, it had other maps that were good objective-based maps as well.