Interestingly enough, Justice Thomas who wrote the majority opinion in the 2005 case that leaves it to the discretion of the FCC to determine if ISPs should be "utilities" now regrets his opinion and has suggested that the court review the implications of that ruling.
100% this. Before the top layer (apps) on the internet get regulated as utilities, the deeper layers (ISPs) should.
Social networks we have a choice. I have lots of friends and family who choose not use certain social networks and the one that he's referring to is Twitter which isn't even in the top 10 of social networks in the US. Most of the USA don't have a choice in broadband providers.
Ostensibly they are. When was the last time an ISP banned you because you wrote something on Twitter it disagreed with?
Public utilities are generally governed by public utilities commissions. These commissions massively control the running of the business. They can affect pricing, delivery, standards, etc. etc.
Denying or allowing service is but a tiny part of the equation.