True Strike is usually considered trap choice (for in-combat use, ie 99% of the time it should be useful) in pnp, as far as I know, for pretty much the reason you said -- it doesn't really do you any good. Even for weapon-focused builds like Eldritch Knight or your Ranger it's pretty much a self-countering choice. In fact I think it's mathematically negative (but please do not quote me on this I hate math and probabilitology makes my treeskull hurt) because I think you are trading two attacks (two possible hits) for getting two chances on one attack (can only result in one hit), meaning that the chance of
one attack hitting is the same in either case, but if you don't cast True Strike you still have the possibility of both attacks hitting and thus doubling your damage potential.
I often see suggestion to deal with this and give it a bit more of an actual impact, like (I want to add that I have no actual experience playing with any of these supposed fixes myself), iirc, either having it last (with concentration) for two turns or two attacks after you cast it, or just straight having it last (still with Concentration of course) last until the next time you hit.
Sometimes I see people saying it should be a Bonus Action to cast it but in my mind that makes it too powerful to be a cantrip for everyone who's any decent at attacks (your stereotypical wizard would be less broken with that because they mostly suck at non-spell combat anyway
).
