Tracking in PvP is absolutely meh.

Not really, does all the work for you. Kind of like the thorn.

Nope, for two reasons. Firstly, you typically don't have time to lock on. In PvP you hipfire RL's more often than not. Secondly, and more importantly, tracking requires an open lane. If an enemy is standing near an object (eg a doorway), all they need to do is move a bit and the tracking will cause the rocket to hit the object, not the enemy. Grenades & Horseshoes will always be preferable to tracking in PvP.

You should try truth then.

I have three. Same thing still happens. Truth works best in open maps and combined arms. More to the point though, it's an exotic. In a choice between G&H and Tracking (legendaries), G&H is the best choice for PvP by a mile.

That's different the truth has a special form of tracking plus if you're next to a doorway just go completely behind it and you're safe.