Figured I'd split this out into a separate comment on the difference in wargame styles.
Releasing new models to help old ones isn't unique to X-wing. Privateer does it all the time with Warmahordes - a new model comes out that is an attachment to a unit, or synergizes well with that unit. They did this from the very beginning - the first expansion added the Monolith Bearer, which took Holy Zealots from useless to one of the most OP unit in the game. So this idea is in no way original or unique to X-wing.
The big difference is that you can buy those fixes as you want, and only the ones you want which directly relate to you. I don't have to buy three units of Cygnar Long Gunners to fix my Zealots. And like it or not, whether you think it's fair or not, most people put the value on the model rather than the cards. So if I don't want the Inquisitor's TIE, buying the cards for my faction feels like a waste.
One thing which is pretty unique to FFG's games is the inability to buy just one faction. As above, this wasn't an issue early on - the range was small enough that playing both sides was a no-brainer. But now we've got a third faction, and coming up on what, 40 ships? Trying to be a completionist and play everything is getting expensive. Lots of people just want to play one faction. Lots may have gotten everything early, but are trying to limit new purchases. The bundling system forces you to keep up with the entire range, which is both expensive and painful.