Namecheap and Cloudflare are registrars, not registries. Amazon does have a registry, but it only seems to offer a few gTLDs and I don't think they're especiall

Namecheap and Cloudflare are registrars, not registries. Amazon does have a registry, but it only seems to offer a few gTLDs and I don't think they're especially popular (I think the biggest is .bot and it has some slightly weird eligibility requirements).