Considering the above scenario where real estate is gaining at 75k per year. A wealthy individual could easily leaver themselves to 75*5 = 375k/yr. Using the starting cost of a home at 600k, this would equate to an average rate of return of about 300%

Such rates of returns are simply impossible in the general stock market without getting very lucky.

You can lever yourself in the stock market too.

Not with 30-year lock-in in rates and with a similar commitment to avoiding margin calls for that long if your bet goes poorly in the short term.