I don't deny that each fighter functions differently, but that has little to do with their described roles. Average engagements have so many fighters that the differences between Warthog, Gladius, Thunder, Broadswords and a few others are impractical to manage, especially if basing decisions primarily on their given roles. You can't pilot more than one carrier yourself. You also have to look at the game from the perspective of occasional and new players. I got the game at 0.7, played every new version since and many weapon and fighter differences are arcane to me. I've been testing (having to "test" game mechanics being somewhat of a chore) different fighter loadouts in 0.9 and "interceptors" often fail to intercept enemy fighters compared to some fighters and heavy fighters in various circumstances, even in 1v1 fights. Once you sum the fighters' assigned role nomenclature, their specific loadouts, different fighter synergies, the limited command points to command carriers with, AI behavior and the chaos of large engagements, i believe an average player finds dealing with carriers little different from "the biggest stack wins". Removing some fighter role overlap won't even solve the issue, but it would start to alleviate it.
The issue with weapons is not as bad, but it exists. I don't think an average player enjoys choosing between early weapons with identical roles and subtle practical differences. (How is a regular player supposed to understand the practical differences between vulcans, the two LMGs and their energy counterparts when wanting an early PD weapon? Having many similar choices is frustrating.) An involved player might be used to the variety, but to me it seems excessive, especially between early weapons.