It’s not. There’s no reason why headphone jacks would be outdated. They carry an analog signal to drive the headphones. With a dongle, you’re just converting that signal from USB-C. USB-C headphones carry the exact same signal and bluetooth is garbage for audio quality. 3.55mm TRS is the de facto standard for headphones in the consumer market. It really doesn’t get any simpler or cheaper.

Every time someone was displayed an ad it made the world just a tiny bit worse

By what metric?

Lemmy has gotten quite a bit of money in grants. It’s safe to say that without the grants allowing the lemmy devs to work on it full time, it wouldn’t be as functional as it is now. Getting grants really isn’t easy and that shouldn’t be the barrier to whether or not you can be compensated for your work.