I don't know. I think the best approach would be to ban surveillance capitalism, (e.g. make gathering personal data illegal), and then new business models would fall out out of the new situation. More likely, old business models would re-appear: selling ads to relevant publications (e.g. video game ads on video game websites), instead of targeted to users; selling products direct to customers instead of funding via ads (this is currently difficult because the surveillance business model out-competes it).
Another approach could be to break up the big tech companies into a bunch of tiny pieces, and hope something more ethical comes out of the more distributed market power & natural competition.
I'm not a marxist by any means, but breaking up the monopoly into smaller companies might make sense. The newspapers before them had similar regulations and faired well.
