Making printers is not trivial. Paper is not as simple as it seems. It's super thin and light which is difficult for machines to handle at speed, and it also comes stacked in a near-solid block from which pieces need to be separated delicately but firmly. The materials science behind the rubber to grip with just the right amount of friction, time after time, accounting for wear and dirt, is mind-boggling. Paper is also noticeably affected by temperature and humidity, both of which change its properties nearly by the minute. This changing nature affects feeding, making the pieces floppier at times and liable to miss the handoff to the next set of rollers, or clingy at others and adhering to a plastic guide for longer than expected. Also the electrostatic properties vary which affects how much charge the drum needs to put on each piece to ensure the correct amount of toner particles adhere -- too much and you get squished smears, too little and the text is faint. And let's not forget the fixing process, which heats the paper to bake the toner into the crevices of the page, which may take twice as long due to extra moisture, but you wouldn't want to burn things if someone is sending through some extra thin paper for some reason. And of course as it's printing the printer is changing all of these variables with its heat and motion, changing the dimensions of every space in its interior. Every printer contains many environmental sensors so they can detect these changes and tweak their control mechanisms for each individual piece of paper. It's kind of akin to baking a perfect baguette every time.
Printers are miniature marvels, and there are still some wizards out there who know how to make them well. But we have to, like, patronize those wizards instead of the goblins of HP or else we will truly be buying our own way into the dismal future of crap that HP creates.
Carly Fiorina.
It was probably the peak for reliability, I worked for a company that sold a lot of them and the failure rate increased quite noticeably when they introduced the LaserJet 4.
Of course, that doesn't make it worth it for just anyone to start making printers. But we see time and time again that where they fail nowadays is in UI, integration, and business models.
It's similar to the post on the first page about USB-C hubs, and graphics cards, and earphones. Typically you buy them as OEM stuff - very very few go through the trouble and design earphone drivers (loudspeakers) from scratch (etc). That, and reference designs. Visiting Shenzhen is an eye opener, browsing Aliexpress too :).
[0] - https://github.com/pdewacht/brlaser
[1] - https://github.com/pdewacht/brlaser/issues/79#issuecomment-7...
[2] - https://github.com/benpye/nix-config/blob/main/overlays/brla...
For printing if you use a modern version of Ubuntu or other distro it's pretty uneventful and network printers, especially those that support Apple print and advertise themselves on your network, all just work.