Geo (and Fyron)
Believe what you will. I have seen plenty of players overreact to the early fighters and overextend their economy, and I have seen some loose vital systems because they dismissed fighters as useless. I have also seen a few guessing just right and neutralized the threath with minimal cost.
Point is: I, as the fighter builder sit with all the cards.
If I build more fighters than you build PDC, I have a potent weapon.
If You build more PDC than I build fighters, You have to pay extra maintanance.
Either way I win
When it comes to late game fighters, it's true they are micromanagement hell. That is why I seldom choose to use them, but it does not mean they are useless. There are plenty of small dirty tricks that makes limited use of them very effective as decoys or weapons. But as I do not believe they are any good as the main fighting force.