If you don't use a VPN I'll note that they have a DNS service that is free. I think this demonstrates some support, at least in the way that increased traffic/usage can be support (and should help make Mullvad VPN users stand out less WRT DNS requests). The only downside I'll say is that the ping time for me is quite a bit higher than quad9 or cloudflare.

I wrote some info about it in this thread[0], including how you can do ad blocking at the DNS level (and cloudflare info for the same).

[0] https://news.ycombinator.com/item?id=40056162