I do share your actual concern, but I think the term 'end user' applies to any human sitting in front of a computer, trying to achieve something, independently of whether the effective sysadmin works against his interests or not.

Every technology has both pros and cons. Those who develop standards must weigh both sides rather than considering only one of them.

In countries where the internet is subject to censorship, as well as in regions with underdeveloped infrastructure, DNS queries are highly likely to be deliberately tampered with, poisoned, or hijacked. DoH is a very practical way to mitigate this problem, and I do not believe that the ability to block advertisements is more important than that.

Moreover, advanced users can still run their own DNS services for ad blocking, and, at least for the foreseeable future, DoH will not prevent them from continuing to use traditional DNS. You cannot criticize an important improvement in security merely because it makes ad blocking less convenient. Other people may face threat models that are a hundred times more serious than yours.

> Who's an end user.

I think in this context it'd be any netizen who does not hold a significant amount of power to influence other [unrelated to them] netizens?