True strike has one good purpose over any other imho:
If you really need an attack to hit, e.g. a hostage situation, or everybody on their last leg and the next attack from the mob which is also 1 hit away from defeat might kill of a PC.
This.
True Strike seems to be more of narrative driven spell in 5e. It's useful in situations when DPR is moot because you simply, absolutely need to hit/can't afford to miss. It's for those story moments when you're outmatched or out maneuvered and you only have one arrow slaying, one application of a highly lethal poison, one tiny window of opportunity to make the critical shot.