You have no need to change from one version to a newer one.
If, however you change your OS to a different version you might need to also update any software you want to use on that new OS.
This is entirely your choice, no-one is forcing you to buy a different version of anything.
Example...
I am still using Windows 7 as my primary OS.
I don't even have Stardock's 'Start 10 or 11' on this particular machine at all.
Similarly I have remained using Directory Opus 10 which was released in 2014 and have not upgraded it as it has been entirely sufficient. Current version is 13.3 but I am happy with 10.