The latter is not necessarily true - you might be creating tremendous value, but have barriers to market entry that are enormous such that you can only really create that value from within one of the existing players on the market. See aerospace, telecommunications, medicine, government contracting for examples of such industries. If I'm making a huge amount of added value for a large telecom, it's unlikely I can start a startup to compete with it, and given the state of the market I'm unlikely to make much more at their direct competitors. Thus, as long as my value is industry-specific, and the industries have large barriers to entry, I might be creating much more value than my salary but unable to leave and compete against my employer.

You make the strong case that your value-creation in such a scenario is an amplification of value created by other people, and is not actually value created by you in a vacuum. What sense would it make for you to claim priority ownership of that value if you can't create it on your own?

You're a component in a value creating engine which includes the ability to hurdle those barriers to entry, which means you don't get credit (on your own) for the total value that you are able to produce within that system.

More likely, you're a resource being extracted by a monopolist that set up those barriers to entry.

Eh, some barriers to entry are artificial, some are not. Even artificial barriers are difficult for a single moustache-twirling monopolist to bring about on his own.

If you can only really create value inside an existing player in an industry with large barriers to entry... then it's actually being an incumbent in that industry that's valuable, and not the employee.

It's like a person making minimum wage working at a hotel in Times Square, charging $800 / night, saying they're getting a raw deal because they're creating so much value.

Right? So many people are looking at company overhead as burdensome, but how are you going to cash in on the $1.5 million in value that you create if you don't have sales and marketing people to get your product out there? How do you even know it's worth $1.5 million if you haven't done market research?

It's not just overhead, it's a highly efficient system.

Highly efficient or not depends on the actual system, ie company. Some companies aren't all that efficient, and have to painfully learn about that fact when real competition shows up.

(See eg the effects of Aldi on the Australian retail sector.)