You say you wish more startups operated standalone. Is it possible that the same person who can build a company from zero to 100 people isn’t qualified and / or wanting to take it from 100 to 1000 people? Shouldn’t it be her right to sell her asset, and start something new?
Some people believe that society has some claim on companies, meaning the government should be able to arbitrarily coerce any company of any size to do anything. Less-logical people claim that society has a claim when a company reaches some threshold of size (which makes no sense as no one can explain what that size is except “eh I guess a billion dollars in revenue”).
The only defensible logic is to let the owner do what they want. Otherwise it’s authoritarian.