AT&T and Verizon have already shown willingness to sell use browser data via supercookies http://techmeme.com/search/query?q=supercookies&wm=false, and the reason they backed off is because the FCC showed it had a spine. There is every reason to believe ISPs will begin these practices again (without requiring opt-in) because these rules have been lifted and Ajit Pai-led FCC is very different from Wheeler's... and there is very little reason for ISPs to fear losing consumer trust because of monopolies/few local high speed options