I believe that .de domains are pretty cool (written another comment about it) but .de are $3.25 for registration and .de is the second most common after .com so from webatla, I see approx 16 million domains.

I don't think that they could ban emails from .de for what its worth.

Personally I like .in domains too. Makes more sense to me because I am well Indian and we all use it quite frequently/sort of intutitively know fwiw but if I just want a domain for email purposes for cheap. Honestly, .de could be good.

https://tld-list.com/ [Try seeing the cheapest renewal rate with top level TLD and ignore .storage which costs 465$ for registration smh]

Some other domains like .top exist as well in this league imo but .de is one of the best if you can find a relevant domain in .de