Companies IPOing should be forced to put up their estimated market cap as collateral in cash. Oh what is that? You don't have $1 trillion in cash to put up? Cool, you're not a $1 trillion dollar company then.
So a simple valuation would be something like Current Cash + Assets + Expected Future cash - (Expenses + Risk)
Failing companies sometimes trade below cash value. OP's basically creating a rule by which only failing companies are allowed to go public. (Or those who have paid a king's ransom to a megabank.)
your suggestion makes no sense