It's an outdated mechanic and I imagine a majority of the community would like to see it gone. It should be as simple as swapping the active Focus School. A long time ago, Conclave Sigils also influenced standing gain and it was shortly removed since people often forgot to equip them so I don't see why it couldn't be done for the main Syndicates. If people had to equip Sigils just to gain standing with Cetus, Fortuna, or whoever else, I guarantee there'd be more people expressing their opinion about them. And much like the reason as for why Arcane helmets are now obsolete, it conflicts with fashion.