I'm hosting my own DNS server with DoT/DoH as reverse proxy of PiHole server. The latency might not as impressive as NextDNS' (7~10ms on my phone via TMobile), and I can have full control of the stack.
I use Cloudflare Workers (their generous free-tier covers 3 devices worth DNS queries, with much room to spare), but the 128MiB RAM limit restricts the number of domains in my blocklists: https://news.ycombinator.com/item?id=22208988
https://github.com/yegle/your-dns