Nothing except not having the capital to do it.
> There's no objective way to say how much "work" is worth
Fortunately I explicitly said at the beginning that my argument wasn't going to involve talking about the value of work at all.
> everyone would just reject his founding
Literally every country up until that point except perhaps Athens had been a dictatorship of some sort. Democracy doesn't just happen -- you have to make it happen. There was no presupposition that everyone should have equal rights before then; that was the innovation of it. There's no reason why that same innovation couldn't be extended into industry.
> Anyone can start a business on a different principle
And anyone can start a country on a different principle. But you have to have a lot of resources to do so, and unless you found it on equality, it'll be terrible for most of the inhabitants. So, given that we have a government to regulate society, I see no reason to let people found businesses based on principles which will lead to such gross wealth inequality.
There's no objective way to say how much "work" is worth - only subjective. This subjective measure is given by the market rate. And in a functioning free market, this should give you consensus as to what some "work" is worth.
> the one to found the country ... people are so unwilling to apply the same analysis to corporate hierarchy.
to have found the country, he could've asked to be a dictator. The problem is that the founding is based on the principle of equality (at least at the time, of men...). So if he chose to turn around and take that equality away, everyone would just reject his founding. People in the country are attracted to the idea of equality, not to the guy named Washington.
However, a business does not start on the same premise - that of equality and rights (for all employees). The business started by the business owner is based on the premise of pay for work. That's as far as the relationship goes.
Anyone (in the USA) can start a business on a different principle - no one will stop you other than natural forces like competitiveness! And i think some businesses do that - a family business for example, which shares the work, and shares all the profits between them (and don't hire employees).