I think it depends on the developer. There's developers hammering out boring business logic as fast as possible and there's developers with a deep understanding of machine internals, protocols, and infrastructure. For the former, SMTP is black magic they'd probably never think of and involves engaging the one infra person that's always busy
It also means standing up and managing "infrastructure"
If I ever heard a dev at work say "No I won't use that new tech, it's too untested/I'll have to spend more time figuring out how to make it work well", I would shit my pants. Whereas if it's old tech, "it's not modern/I'll have to spend more time figuring out how to make it work well". It's practically software ageism...
I tell you that as someone who fiddled with sendmail.cf’s and other .conf’s way too much long before nodejs became a thing. Now it’s a relief.
Purely anecdotal of course, but I follow a number of the latter, and they're either sparsely employed or often employed in a capacity where it doesn't matter There was a comment in this thread where one person had such an idea, and it was rejected for what were essentially business reasons.