I'm with you on weak Glock extraction and ejection but relying on the synergy of multiple components for those functions is part of the price for a minimalistic system which functions with a minimal number of parts i.e. a Glock.
My duty Gen 4 17 ran fine for the first 7k rounds then started BTF and FTE. It took a HRED and a new ejector to get it 100% again. Regardless that does not make the 10-8 test relevant to Glocks. They just are not designed to function that way.
Having carried and observed multiple examples of both Glocks and HK USP Compacts, peak function of individual components = HK :-)