"What exactly are the practical consequences of being spied on by GMAF, compared to law enforcement?"
Should law enforcement order them to relinquish all data about someone wrapped in a gag order, they get all information they need without that someone even noticing.
I think I am not of interest to LE today, but who knows what could happen in a few years from now. Should the wrong people get in power I don't want them to know what's in my head as much as I don't want any potential employer to know about my ideas.
The point is that whatever information they collect today about people, it stays in their servers forever, ready to be scraped through AI to build a profile.
Should law enforcement order them to relinquish all data about someone wrapped in a gag order, they get all information they need without that someone even noticing.