This discussion doesn't pertain to the game's progression like upgrading a gun or jumping to the final boss does. This pertains to cars being locked away, which don't pertain to the game's progression.
I'm fine with racing events being locked away until you complete a license because that's part of the GT formula, and it follows with other games where you unlock the later content as you progress. However, i feel that locking content away, that's not part of the progression, is silly. There shouldn't be exclusive cars. Exclusive liveries are fine. Exclusive achievements are fine. Requiring that challenge in order to get 100% is fine. Not being able to purchase/acquire a car because someone doesn't want to do some challenge for whatever reason is silly. The only reason we should have hard challenges is to make it easier for those who took the time to complete them. Get all gold in the Super License? Hand out a car that will be useful in some of the S license events, or hand out one of the more expensive cars in the game.
I understand the opposing point of view, I really do. I found it okay in GT3 and it was a little annoying in GT4.
What will I do if they reintroduce cars exclusive to beating challenges? I'll suck it up and beat them since I want 100%, but I won't like doing it.