The UK does have net neutrality, and it's quite strictly regulated by Ofcom, which produces an annual report showing compliance and highlighting any issues it has investigated:

https://www.ofcom.org.uk/internet-based-services/network-neu...

Things like restrictions on tethering and using a SIM in a router are forbidden.

Unlike most countries, net neutrality has never been a political football in the UK.

Ofcom groups zero rating schemes into three types:

Type one - government and NGO services (always allowed).

Type two - where categories of service (e.g. video or music streaming apps) are zero rated, but any service fitting into the category can apply to be zero rated by the network.

Type three - any other kind of zero rating.

Things like the VOXI Unlimited Social Media packages fit into Type Two, so are expressly permitted.

For the rest, Ofcom assessed the impact on consumers, which is generally low.

This is not net neutrality, all network traffic is not treated equally.

Ofcom seems to have invented their own definition of net neutrality and placed it on that website, but calling a tail a leg doesn't make it a leg. This is tiered access.