In the prostrideskatinglabtoronto Instagram video Pavel Barber quickly goes through four profiles from the Elite Profile machine. Nothing that useful but one interesting statement jumped out. He started with the 9'/10' and said, "...this is the most popular one in the NHL." So, whether that's overall or just based on the dataset of their users, it's interesting. This is the only one that I have ever heard there is any data to show it was better than other profiles it was tested against. Was it @oldtrainerguy28 that was part of the study or cited it here before? I have also seen a presentation from ProSharp where I am pretty certain he said most of their NHL skaters were on Quad 0. That was definitely from a few years ago.
Just a data point. I still believe profiling has a big effect on skating, and can be beneficial, but I 100% believe that there are too many, they aren't validated, and for the normal retail consumer, there is no way to match profiles to players based on "talking with the pro shop tech" or filling out a form.
When parsing all this overinformation years ago, I decided to just put my son on 9/10. It was the only thing there was any data on. So I figured I would baseline there and at the very worst would have consistency. It has worked out well. I'm not chasing profiles and he has never had an issue. One skate change (strangely from Supreme TO Vapor, but that was the last year of youth sizes so not sure how those sizes actually are pitched) he immediately felt too far back. Small shim and we were done.