As far I understands and I was told by some successful entrepreneurs that startups must not assume that it can build a great team by paying them less.

Actually, when growing the team, startups must assume that they will pay more than competitors.

Paycut is ok if it is augmented with generous equity (really generous): which basically means first couple of employees. And startups should treat these early employees (which took paycut) as important investors and co-founders.