The ACLU will absolutely oppose this. If not for the reason they stand to make a lot of money suing ISPs for "not doing enough" to stop the big-ole-meanies online. I see ISPs blocking "mean speech" to "protect people" as another symptom of the enshittification of the internet. I legitimately cannot understand problems in this arena because you can just...walk away from your computer. Or turn off the website. Or hey,…
I take it that (a) your income doesn't depend on your internet presence, and (b) you're reasonably well off. KiwiFarms has done massive damage to people in "the real world", and some people concerned for their safety cannot afford to ignore it. It is a genuine danger.