What are my options for ensuring that water pressure doesn’t drop in the top floors when taps in the lower floors are opened?

In many multi-storied buildings, I've noticed that the water pressure in the top floor taps reduces drastically when the taps on the lower floors are open. I'm currently in conversations with the builder deciding on the plumbing for a house under construction. The water source is an overhead tank.

What options do I have for making sure that the water pressure in the top floor taps doesn't reduce when the taps on the lower floors are open?

Will separate outlet pipes from the overhead tank to each floor help? If it is a single outlet pipe from the overhead tank, will reducing the diameter of the pipe as we go lower work? The option being suggested by the builder right now is a pressure pump – is this the only option? I don't particularly like this because I trust gravity more than electronics, plus it feels like a waste of electricity as well.