It will if your device speaks QUIC; you can configure your browser to talk to that device. But I do think it makes much more sense to make the browser just do

It will if your device speaks QUIC; you can configure your browser to talk to that device. But I do think it makes much more sense to make the browser just do the job directly, rather than delegating that to a separate device. Firefox continues to block ads just fine, and it'll keep doing so in a QUIC world, while protecting me even more from malicious local DNS servers. The average person is much more likely to encounter a hostile DNS server than a "helpful" one.