My understanding is that basically all clients were scaling to the next highest integer factor, and then rescaling back to the fractional size. With this, and support in the toolkits, it should be possible to be more efficient and have more accurate rendering.

But yes, I have a keyboard shortcut that can change the scale of my entire desktop up or down in .1 increments. It's one of my favorite Linux things because macOS and Windows sure as hell can't come close to working that well with arbitrary scale factors.