The term "retro" itself doesn't even really mean "old", it just means something is imitating the style of something older from 20 or 30 years ago. Just look at clothing for instance, "retro style" clothes could have been designed yesterday as long as they emulate an older style. *Vintage" clothes would be actual old clothes that were produced a long time ago

What I always find fun is when open-source communities just continue developing games forever, defying this whole idea of old vs. new. NetHack is quite possibly the oldest example, which had its roots in Hack around 1982. And it's still being actively developed, still getting new content. So, you get the retro gameplay and long history of the game, while also getting continuous updates like you'd get in an Early Access title. 🙃