Actually that's not correct. Fusion has never had a free version for the mac until Fusion 12.
The point is that Fusion is a relatively cheap piece of software that requires extensive development support - that combination means more frequent paid upgrades. VMWare makes no secret about that, yet every time Apple has a new release (or more accurately, about every other, since Fusion has been doing .5 free upgrades fairly frequently), this complaint comes up.
Fusion has vastly deeper integrations with the operating system than almost any other software. In recent versions, especially in Big Sur, Apple has made massive changes to how the internals of the OS work, and that breaks things (and did, badly, for big sur). It'll get even worse for the next version, and let's not even talk about the M1 migration.
I pay a subscription for most software these days, so the changes required were baked into that cost (Adobe for example). Software that didn't have deep integrations with the OS, didn't even require an upgrade. My firewall certainly did (which I had to pay for), as did disk utilities (which I also paid for), and a couple of other more esoteric applications as well. Some of my software *still* won't work properly with Big Sur, paid or not.
In the end, all commercial virtualization software has basically the same business model (Fusion's is actually the most generous). When things change, charge the customers to fund coders.
