We have very hard water in London and I don't have a water softener. You work out ways of getting a good lather nonetheless, significantly easier if you buy excellent products.

Whenever I'm away from home, the water is nearly always softer and I find it makes a huge difference to how soft or hydrated it makes the beard, and therefore how much smoother the shave is.

I think water softness can make a big difference, but you can still get great shaves from hard water.