Now, if Ableton ends up being acquired by a private equity firm, you may very well see a shift in their pricing model where extracting revenue from customers at the expense of product quality becomes primary.
If you have worked with any of the people currently, or formerly, running Ableton, you will know that they worked hard to regain their financial independence from their outside investors and I doubt becoming a predatory software subscription service is on their roadmap.
There is very little reason to upgrade to the latest versions IMO
The model just works because you don’t need to upgrade constantly, it’s nothing like a subscription.
Ableton makes this extremely clear in:
https://www.ableton.com/en/live/compare-editions/
go through it and you'll see that Standard is the least you'd want, and Suite is a great deal.
IMO that's a better model for consumers since you do get something at the end of it. And if you are a professional, you were probably already getting the latest and greatest every time anyways.
[1] https://www.ableton.com/en/rent-to-own-ableton-live/