That post wasn't about legislation. It was about the fact that if Comcast started trying to install root certs on the machines of customers using them for their ISP (which itself is unlikely because of the extra cost both to install, and to troublehsoot, i.e., "why can't I browse anything when I am on my new phone"), Google, Apple, and Microsoft could, and likely would, decide to reject them in their respective browsers as being untrusted. Because they have seen fit to do that in other instances where user security was compromised, and an ISP MITM every bit of your traffic is no less alarming.