This is a silly take on the situation. It has nothing to do with "net neutrality", unless you define "net neutrality" is "anything I don't like, especially those things I haven't thought through".
2/ Net neutrality is more usually defined as a lack of government regulation that allows an ISP to filter content. The opposite problem is happening here: it's too much regulation requiring ISPs to offer content filtering.
3/ Intercepting DNS like this is NOT "unethical", unless of course you define "unethical" as "anything I want it to be". If an ISP either blocks access intentionally, or when the network accidentally fails, intercepting DNS is an acceptable way of dealing with the problem.
4/ It's not a GOOD way anymore, as DNSsec, DNS-over-TLS/HTTPS, and public resolvers make apparent, but it's not unethical.
5/ Intercepting DNS, including invalid DNS names, for advertising purposes is probably unethical, though.
