By far most ink cartridges come without heads. The heads are mounted in the printer itself. Even if the head is on the cartridge the controller can still be in the printer.

A couple people have said this now, but can you link some examples? I’ve been watching the channel for a while and don’t recall things like that, but it could just be that I was watching with rose colored glasses.

I feel like I have to point out that Xorg is neither unmaintained nor deprecated. It is old as tits though.

Which is why for a lot of serial protocols nowadays they changed the labeling to MOSI/MISO instead of TX/RX