There is a high probability that you are using a proprietary operating system in your computer, whether it’s macOS® or Windows®. Perhaps you are used to your current system and prefer not to switch to GNU+Linux.
There is good news. Most of the free software in GNU+Linux is also available for macOS® and Windows®. You can install free software for macOS® and free software for Windows®. You can adapt yourself to use them on your own system. Then, if one day you decide to install GNU+Linux on your computer, the transition from one system to another will be easier.