You're conflating financial "capital" with real productive capital here. In real terms, non-productive financial assets simply do not matter; whether landlords extract a billion or a trillion dollars makes not a whit of difference in the real goods and services the economy produces.
If you redirect financial assets from bidding up the value of housing to bidding up the value of small businesses, you've simply moved the siphon from cost of rent to the cost of owning your own business and/or suppressing wages.