Just as another data point: I have been looking at it like you in the past, but now I’m getting old enough that I worked with enough engineers to realize that whole experience has a general correlation with seniority, there is a huge variation between individual.

I have in mind one of the most skilled and mature engineer I have ever collaborated with who has less than two years professional experience. I also worked with many 10y experienced folks who qualify as senior for this, but were pretty sloppy otherwise.