There is Yandex Browser [0] which is based on Chromium and exists since 2010. Its share in Russia is ~33% while Chrome has 42% of the market [1].
[0] https://browser.yandex.com/
[1] https://gs.statcounter.com/browser-market-share/all/russian-...
I guess my broader point is we might need something for regimes that are willing to instate varying degrees of isolation. Like, "so your Internet is controlled by authoritarians; now what?" Not to imply there definitively is a thing--that xkcd about the wrench is the dominant principle ofc.
at least none of the major websites on the internet do.
To get ECH to work for me I had to enable DoH in my local Unbound DNS daemon and point Firefox to it rather than using unencrypted DNS on my LAN. I had to force a refresh (shift-F5 on tls-ech.dev). I only use my own recursive DNS so I get query logs and can block some ad/malware sites.
[1] - https://crypto.cloudflare.com/cdn-cgi/trace
[2] - https://tls-ech.dev/