You are correct in what you are saying.
I was just pointing out that:
a) Fusion 360 does exist and may be an alternative
b) It is powerfull due to combining different manufacturing aspects
c) Many of the concerns (like the ones you mention) may not be that important: Cloud based is probably as secure as using files locally (they can be victims of ransomware for example or you can delete them by acccident or the harddisk may fail, etc.); commercial application may be closed source subject to licensing, but then a typical project is developed over the period of 1-5 years - who cares about the files after that? And why should Autodesk or any other vendor stop selling their products?
Finally, when you are using free/open source software, who will you complain with, when the software does not work as expected? Having access to the source code hardly means you will be able to do somthing with it, unless you are a programmer - in which case you will probably not be using the software as a user.
Anyway, I don't want to start another discussion on free vs paid software, cloud vs non-cloud, subscription vs perpetual, etc. I agree that subscription is bullshit for the user, as you are in the hands of the software provider. But: subscription will be the future for most if not all commercial software products and if their productivity and functionality is much better than equivalent alternative software that is not subscription based, you are screwed, as you can choose to be a) dependent on subscription or b) less productive.
And yes, software companies adopt subscription due to the sole reason of maximising their profits and to have consistent flow of income, which values them in regards to shareholders.