I can't comprehend why you think ISPs would feel compelled to be so altruistic without any government intervention.
Except, since when was free wi-fi an impossible thing to find? Ever been to a coffee shop? Even in the "free shitty half-internet for everyone" pipe dream, the costs of such a service don't just magically disappear. Either way, someone's paying for that free internet, and it isn't the ISP.
Telecoms likely didn't deploy anything because this was obviously going to get overruled by the next non-Trump FCC. Even Ajit Pai has a long record of advocating for modernizing the FCC, which would explicitly involve the regulation of internet services. Abolishing net neutrality is only universally popular among communities where the underlying philosophy is "government is bad, and I'm gonna prove it by running it badly."