I feel that builds the argument that they should be implemented more widely, not abandoned. Also, ISPs are targeted specifically not because people believe they are malicious actors, but because they are literally the gateway to everything, impacting you just about any time you use the internet. Think how much it would say about you as a person in detailed logs from your service provider.
Regarding your analogy, end to end encrypted content is not readable by the ISP, they can see metadata for encrypted content, but not the content itself. Whereas webmail providers can see the content[1]. Another example is Google who run a public DNS server. Another example is Apple keeping all phone numbers[2]. So the data that edge providers have access to(in theory) is fairly significant. I think definitely to be consistent the law has to be an all or nothing kind of thing.
[1] https://techcrunch.com/2016/10/04/yahoo-scans-email-for-nsa/
[2] http://www.macworld.com/article/3125570/iphone-ipad/apple-ke...
Meanwhile, most US households have only one option for 25+ Mbps Internet service because the FCC dismantled competition among residential ISPs. If ISPs don't want the responsibilities that come with monopoly power, they should stop fighting to preserve it.
[1] https://www.fastmail.com/about/privacy.html