I always considered fighters in Star Trek as something that keeps getting tried on occasion but then usually discarded for the same reason, in that the return of investment isn't there. In the case of Star Trek, I doubt you could put enough oomph into a one-man craft to seriously threaten a good-sized Starship.
You know, a bog-standard Photon Torpedo would have a maximum yield of about 64 Megatons. Quantum Torpedoes and high-yield Photons are even higher...
Even without including non-expendable or exotic weapons, that's quite a bit more than the punch-to-weight ratio of the torpedo bombers than sank Yamato. 'Probably less personnel-wasting to send out a 2-man fighter than an 80-year old exploratory vessel to get a couple of torpedo volleys off before getting cut in half. You could even send fighters out in multiple angles of attack. A...multi-vector assault, if you will.
Of course, ribbing aside, and in all seriousness, making completely rational use of established technology in Star Trek is A) difficult to execute on a (live-action) TV budget and timetable, even if you give Ron Moore extra time to figure out what to write, and B) would likely interfere with the tone and general type of stories the creators want to tell (which happen to be Sgt. Sisko's Amazing War Stories). 😁