This is just a timing issue. You can already get every device like mice, keyboards, headsets etc with USB C. If you've never seen one, perhaps you're not getting out enough.
As for RS485? That's _forty years old_, well done, you're a hipster outlier and that has nothing to do with anyone other than 3 people anymore. Come on, that's just a stupid analogy.
If you want to use decades old tech, congrats, you get a dongle. Stick them on the end of each USB cable/device, they're a few mm long, you won't even notice. I'm still running a motherboard and CPU from 2011. I'm not exactly Gen Z. It would be idiocy for me, or you, or anyone, to be insisting on USB A devices now for no better reason than "well I haven't seen a USB C mouse yet"
(and that's because they're bluetooth - god you're going to be furious when you hear about that)