The obvious long-term solution is to obtain the .bun gTLD in the next round of applications (expected 2026)

there have been discussions about this

Another vote for same TLD. I’d dare say this should be the default position for everything (except toy projects).

I don't know if it's unpopular. That's literally how domains are designed to function and have done by and large for decades

I think marketing folks like to send emails from a different domain so they can send transactional and marketing emails from different domains altogether (not just subdomains). Not sure if this is evidence based or just plain voo doo / monkey-see-monkey-do but I’ve read this in multiple places. But of course, that doesn’t apply here.