Typically the founders don't have 65-80% of the company, some future investor does.
In a typical startup, the ratio of equity between founder and employee #1 might be 50:1 or even much more. I am always surprised that people sign up to be employees given how fast equity grants drop for every subsequent hire. And, I wonder if any company has tried more gradual equity drop-offs. For example, where the ratio between founder and early employee grants is < 2:1, for example.