Dude, you’ve drank so much kook-aid you can’t see the truth.
I’ve personally had had every type of custom liner except Zip-fits and every brand of custom insole. Ive hade multiple of each all molded or fit by the ‘best’ custom boot people in the Salt Lake Valley. None of them made my skiing noticeably better, and in more than one occasion they made my situation worse. On top of this, I am not the only one. I have multiple friends who have had similar experiences. This is not just an n of one. You know what I’ve had the most success with? Stock shells with softer foam intuition liners that I DONT mold, but ski into shape.
And I hate hate hate to be that ‘claim’ dude, but I will assure you I am skiing in a plenty advanced manner.
Finally, do you know how many pros are in stock boots that probably aren’t the best ‘fit’ for them. They often have to ride what their sponsors send them, not they they would choose. They all do fine.
Again, people can and should buy all this stuff it it’s what they want. But shop people and bootfitters also need to be realistic about what it is, marginal gains at best.