>If AT&T terminates customers’ access to websites, customers will go to Verizon etc.
I'm not sure if you're familiar with the ISP market in the US, but the point here is that there are many areas in which customers cannot switch to another ISP. If AT&T were to block websites, those customers would have zero ability to access them. Hence the "some companies are too big and influential" bit.
I support net neutrality and think internet should be a utility and treats all websites the same.
But if a website is willingly violating terms of service defined by the provider (hosting child pornography, spreading racism etc), I support the IPS to block access or whatever.
The fact that some users have no alternative is another problem.
If AT&T terminates customers’ access to websites, customers will go to Verizon etc.
If all providers blocked access, they must have a good reason.