Huh? Other than the example that @CptLucky8 posted above, which I didn’t even know existed, every keyboard I have ever used myself is of the on/off variety. Mechanical, rubber-membrane, they have all been on/off. They make different sounds, but that’s about it. I have Blue switches at home in my DAS Keyboard mechanical at home, and I use the same keyboard with Brown switches at work, as well as the 5Q with the Gamma Zulu switches. They are all on/off, no matter how enthusiastically I press them.
What traditional keyboards are you referring to?