Thank you for the clarification. Tuxedo OS is based on Ubuntu with the KDE desktop on top, that may the reason why it runs more recent versions of Qt.
Out of curiosity I checked the Strawberry Player on my Mac, it runs with Qt6.10. So the Linux/Ubuntu version is a bit behind.
So for the time being, I have installed Clementine on my Tuxedo machine, it's a bit dated, but as it only requires Qt5.X, it runs.