That's not correct and the law is clear on this respect. No one has standing to sue you if you decide to sing in public a Michael Jackson song. However, the moment you start selling tickets to the presentation, that's something entirely different.
You are literally leveraging the fact that someone put that song on the map. You didn't create it. You didn't promote it. You didn't do anything, in fact, except try to profit from it.
Libertarians still believe in property rights. Property can be tangible or intangible.
The point can easily be made with a simple peek into history. No one that recorded anything intangible, like a song, was selling it to others for commercial use because they didn't understand that intangible they had just created had value, but the moment they did, morally, they felt it was wrong and sought the courts for redress. There are examples in history:
In fact, the oldest documented examples of creators pushing back against unauthorized copying predate any formal copyright laws by centuries anda few stretch back to over a millennium! [1] [2]
[1] https://www.plagiarismtoday.com/2011/10/04/the-world%E2%80%9...
[2] https://course.oeru.org/oerdsc/copyright-and-licensing/copyr...
Why is this important ? Because the oppression you mention of freedom, in order to happen, must be codified by government. If you have this issue going so far back in time, when government hadn't codified anything, its a clear indication that the issue trascends code and goes to the heart of what is moral and inmoral.
This debate of whether you own an idea, trascended the codification of the idea in government "repressing your freedoms" . The fact of the matter is, we believe strongly in freedom, as long as it doesn't transgress the freedoms of others. This is key. In this case, the freedom to reap the rewards of your hard work should not be infringed by the work of another. You are not more important than someone else. This is a basic tenet of liberty