Disney profited from the works of the Brothers Grimm, Hans Christian Andersen, Shakespeare, Osamu Tezuka, European and Chinese folklore, and many more sources.

Great artists build upon the work of those who came before them. This is how it’s been for millennia. Why should Disney be the end of the line?

That's the thing about the public domain; it belongs to the public, not to any one company.

I doubt you have any problem with people profiting off of Shakespeare, Mozart or fairy tales, so what is different about Mickey Mouse?

How many of Disney's cartoons do you think were based on public domain works?

This is actually the natural state of affairs. Intellectual "property" protections are a relatively recent invention (15th century) - created in theory to encourage production of more intellectual property and abused in modern times to provide eternal rents to owners.

Disney created the character and was able to profit from it for years, but Disney has equally profited over characters it didn't create but instead created their own adaptations. Why should other companies be denied the same thing Disney had access to?

How do you feel about people who didn't create the English language being entitled to profit from being able to speak English?

We progress because we're able to build on what previous generations built.

Why should modern shareholders of the Disney corporation earn all the profits from what some people did 120 years ago? What good does that serve?

By the time I was born Mickey Mouse was so embedded in popular culture that it would be unreasonable to expect me to avoid the character. I certainly won't be telling my daughter to choose which characters to like depending on the state of so-called intellectual property laws, that would be absurd.

All this adds up to the fact that established characters are already effectively part of the public domain. A perpetual monopoly on children's culture is both unnatural and unjust.

Disney still benefits from trademark law on their characters along with a generous monopoly on new creations. I would argue that extending this further would reduce the incentive to innovate.

I don't know what the parent poster had in mind, but in my view losing most control by now is absolutely right and proper.