Just to add perspective, I work in the US and our office bathroom sink does not have a mixer tap. I'm in an old building in an old city and the bathroom hasn't been updated since, well, at least since the early 1900s.
My US 1980s office building doesn't have mixer taps in the restrooms. I've always suspected they just want us to use the cold water. With lots of liquid soap, it works just fine.
Indeed, I'm pretty sure that the WPA-built classroom building that's recently been torn down didn't have any hot water: one tap in the restroom only. (No one with tenure ever had to teach there, so I'd have to check with a grad student to be certain.)