If we accept that neutrality regulation is unnecessary in the UK due to the effectiveness of the market that exists here, we should remember that this market itself exists because of other forms of regulation which have been imposed, including: the ease with which customers can switch ISPs, publishing official figures of the frequency of complaints about ISPs, the incumbent telco being required to provide wholesale internet access (with price controls) which can be resold by any company who wish to set themselves up as an ISP.

It seems to me to have done reasonably well at encouraging suppliers to compete on price, and on customer service quality (provided you don't take the ISP's word for it).

It hasn't been great at hastening the widespread availability of > 20Mbit broadband, and that is probably in part because of a particular technological and financial internet access model becoming somewhat entrenched, due to the very same regulation.

I tend to be of the opinion that net neutrality is a useful tactic where a functioning competitive market doesn't exist, and is beyond hope of being made to exist. Outside of that, I'm much less certain of how valuable it is.

(I'm not going to address the whole UK internet censorship and data logging thing, because it's orthogonal to the structure of the market. And also because it's really fucking depressing.)