No, USB HID API can have all 104 key rollover if you want. The urban myth has something truthful behind itself, as at some point Windows refused to work past some number of key rollovers, and then keyboard makers started to limit it to accommodate Windows.

Where are you getting this stuff about Windows from? Everything I can find says it's because of BIOS limitations, nothing to do with Windows; see https://www.devever.net/~hl/usbnkro , for example.

> then keyboard makers started to limit it to accommodate Windows

Wow, I really had no idea. That's really frustrating...

Any way to fix this? Maybe we can somehow hack the keyboards. They have an USB controller with firmware on it, right?

USB capable microcontrollers are a buck or two in unit quantity; most of them with a USB drivers fron the manufacturer have a HID device as a standard example. It's like "Hello, World!" but for USB.

Hack? Nah. Engineer? Easily.

But the other commenter who noted that it was a BIOS limitation was right - it's not a Windows thing.

Have the keyboard maker order a controller chip that does HID in a way compliant to spec