Now look at their rules, not their obscure EU character names. Lorrir might not have been very impressive in a random EU story, but a TIE interceptor that can barrel roll with a curved template fits the "ace" archetype very well.
Are you saying it's impossible to have an ace Y-wing? A lot of rebel pilots would disagree!
The ace packs are FFG's equivalent of the big boxes in Netrunner where they add a whole load of new options and stuff to one corp and one runner. We've had the TIE Interceptor Acepack, the X-wing Acepack was in the transport, and Rebel Aces is ace treatment for the A-wing and B-wing. I've little doubt they'll continue to make these. We call these packs "aces" not because they're aces necessarily but because the first pack to do it was Imperial Aces and Rebel Aces follows in the same vein.
You're correct in that thematically Rebel Aces is about the elite pilots flying the rebel prototypes, and the Y-wing isn't a rebel prototype, but you're fixating on it to the point where you're disregarding other information. Let's say the Y-wing isn't a good fit for a pack about rebel ace prototype pilots, and that if they swapped the Y-wing for the B-wing now the pack's theme may be somewhat damaged. But that's assuming they'd design the pack with the B-wing and then swap in the Y-wing. They do thematic design and branding after game design. If they made an A-wing and Y-wing pack and decided the Rebel Aces name didn't fit (I personally think it would fit fine) they wouldn't think "We can't use the Y-wing, it doesn't fit", they'd think "We can't use the name Rebel Aces, it doesn't fit." They name the pack after designing it.
This means the whole ace thing is wholly immaterial. What we're saying is that we wish they'd have designed it as an A-wing and Y-wing pack from the start, that the Y-wing is in more need of some fresh life than the B-wing. Why did they go with the B-wing? Any number of reasons: they had good ideas for B-wings then and not as many for Y-wings, they wanted to introduce their B-wing mods to the current meta and are holding back the Y-wing mods for the Wave 5 or 6 meta or the Imperial Huges, the Y-wing mods use new mechanics they intend to bring in in later waves, they considered the astromechs and torps from Rebel Transport to be a sort of "mini-Y aces" and thus decided to handle the Y-wing, they planned Rebel Aces before XXBB became dominant and didn't know the B-wing was going to be so good, they figured the Y-wing would go better with a TIE advanced in a Yavin themed back, any number of perfectly good reasons for it. But I don't think for a second if they wanted to do the Y-wing that the Rebel Ace title would have held them back.
Edited by Lagomorphia