I don't agree. I think he did the right thing. Living aliens worshipping Enterprise or dead aliens. Which is best ?
If you've got the glass ball that lets you see they don't turn into a world full of Reavers or Breen or Imperial space nazis, that can justify intervention, assuming you are willing to play God with history. But revealing the giant metal bird to them at an impressionable time is monstrous.
Kirk might be condemning them to millions of years of religious strife, and I don't know that is better than letting life evolve anew there after the volcano plays out (assuming it really killed everyone, which sounds a little O-T-T ... is the volcano going to cause non-nuclear winter for the whole world?)
EDIT ADDON: I should acknowledge that I personally find TREK's prime directive ridiculous, utterly unenforceable with respect to outsiders (what good does it do if Starfleet can't interfere, when other humans and any other race can trot in and interfere with any of these worlds? None at all. And if Starfleet actually cordons off these systems, then that is a full-time operation with everything they have, just to keep these natives from getting poached by Ferengi.)
The real bullshit aspect to it is the cavalier way THIS Kirk dismisses it, like don't worry about it. So this is the GENIUS Kirk talks about in the first one? And yet he doesn't understand the potential consequences and certainly doesn't appear that he is going to be haunted by them either? If Kirk is all that intelligent in this timeline, then you shouldn't be playing him for a dummy.