Consider the fact that every time you buy a house with a 10% downpayment mortgage, you're taking on 9x leverage. The fact that banks are willing to lend you ~$500k at a ~4% interest rate, on a piece of real estate that can produce >5% returns (including rent), is often what makes it such a fantastic investment.

The same principle can be applied as well to stock investments. Obviously a 9x leverage would be too risky for stocks, but a 1x leverage is reasonable and can easily lead to win-win outcomes for both lenders and investors.

If you're worried that unsophisticated investors can misuse this feature - there's nothing stopping such investors from putting all their money into a single penny stock either.