Where did you get this information that an investor gets 0.6% monthly? This is some kind of nonsense.
That's his example that for someone to earn $600, that investor should have at least $100k for that percentage of average.
Today, no one gets less than 15-20% per annum. In my country, even a bank deposit gives about 21% per year of the deposit. Now imagine that other assets give it. Therefore, you wrote complete nonsense that does not fit with reality. You should study this issue in more detail.
It varies to what kind of investment and deposits that we get in. In most bank deposits, it won't even reach 21% per annum and just like from 1% to 5% so that's even more unreal when you've said 21%. 15% is possible and lower of it are the typical rates for most but they're not mostly banking deposits that gives that typical rate.