Its not entirely broken but I agree warlocks are a little... not great right now, in fact they are the worst class right now sadly, especially with no multiclassing.
Be straight up: they are garbage.
And yet, virtually every other stream I watch, people are playing them, even asserting they OP.
669.6 hours of playing SOLO playthroughs, testing SOLO builds, equipment and weapon(s) load outs for those build, etc. And I have yet to SOLO EA Act 1 with a warlock (but it has been done from one or two players that I know who likewise only play SOLO). SOLO warlock is an utter pain in the arse when compared to all the other classes currently in this game that can SOLO EA Act 1 with relative ease. Maybe once they hit level 5, maybe, I dunno, will see then.
