...the phono cables from Purist are constructed using substantial (thick) mechanical vibration shielding as well as the customary electrical shielding. When cable designers include this feature, background and/or noise floor seem to get blacker and detail comes forward
Maybe yes, maybe no. It has absolutely nothing to do with Quality. Cheap foam inside makes it thick but has no influence for sound quality. Purist has thick cables and very simple thin leads inside :-)
Good phoncables should show some Physical knowledge and low capacity. Most don't have a dedicated "Phono" Cable, they re-brand a normal NF Cable, double the price and that's it.