I don’t think this is a bad idea but promotions are often very circumstantial and cannot really be normalized across companies.

Meta promotions for instance generally happen faster than Google. This is to say nothing about the actual quality of the person being promoted.

Other companies promote strictly with tenure. Unfortunately promotions are generally zero sum. As a hypothetical if everyone who is in the industry used this the main effect would ironically be making it harder for some poor sap who isn’t using this to be promoted as the bar is raised.

This is a good idea but I’d probably still prefer to find trusted people within my org and outside my org who’ve been promoted once or twice and are one, at most two levels from me and solicit their advice.