1: If all or even a large fraction of bank clients( beyond the RRR) try to withdraw at once, the money is not there. That necessitates it is not real in any sense but imaginary.
2: Fractional reserve lending necessitates private banks basically render new money, causing inflation that steals the value of money from independent savers/ investors. Inflation is theft writ big. Inflation also incentivizes people to spend rather than save or expend to avoid the depreciating impacts, at the cost of their long term financial stability.
It is a Ponzi/ pyramid scheme by globalist bankers. Simply a very early participants who produce the bubbles benefit at the expense of genuine savers.