Yes you can add entries, but it's still an awful design. It's like if the web didn't have media queries and such and instead everyone ships a big database of user agent strings that websites check in order to know what features they can use.

And no, caniuse or browserlist are not that. Yes they contain data on what browsers support what, but that's only to guide your compatibility decisions. You can still opportunistically try to use a feature and a new browser that's not in the DB can handle it correctly without having to lie in its UA string.

> It's like if the web didn't have media queries and such and instead everyone ships a big database of user agent strings that websites check in order to know what features they can use.

Do remember that both the interface (the terminal) and the software environment is under the control of the same user. And terminfo is more of a translation layer than a database, more like the Linux virtual filesystem which hides away the different filesystem implementations. Or ALSA and DRM.

Going back to the issue on the software side, many time, the only check they do is checking if stdout is a file or a tty. If it’s the latter, their output is full of color and spinners, no matter if TERM is explicitly ’dumb’.