As an experienced developer, I struggle to imagine any of the talented younger developers I've worked with being well-represented by a number that quantifies their experience.
I take issue with any hiring system that attempts to narrow the field of view of candidates. This includes any single-number "scoring" system, as well as hiring cultures that focus on single methods (e.g. "puzzle questions") to the near exclusion of other hiring criteria. If your organization is doing any of the above, it's shooting itself in the collective foot.
The problem is not the talented younger developers. It's the not-so-talented ones. At least they keep us old guys in business to clean up the mess afterwards but this is quite a problem in some fields. The talented younger developers are doing quite well by themselves. I get to meet them in small groups every now and then and some of what I find blows me away.