.email TLD is around $25/year, which seems too expensive when .com is less than a half, but it would make it easier to explain why there is no website behind my domain (as I just want something for email).
But there’s also more expensive options, so I am curious what you’re paying.
I’ve never had anyone say anything about the domain not having a website, so go for anything. But I pay around the same as a coffee per year per domain via cloudflare.