Perks don't mean much after a point, last time I looked I had 17,000 perk points. I don't often fly a perk plane just because I don't see much reason to. I can't stand the 262, the only perk plane I ever fly is the Tempest. But, I am probably a minority, I know many, just in my squadron, keep their perk account at zero for the most part, 'cashing' them in on a 262 or whatever as soon as they have accumulated enough points.
I think for most people they represent an 'option' to be uber and as such have some value, whether that value is potential or actualized really doesn't matter. Just knowing that that 10 kill run in a P40B earned you enough perks to fly a jet until you die in it is incentive enough for many.
Zazen