“this move was driven more by software development cost concerns than anything else”
Problem for Adobe is that Photoshop and related products are too good. It is becoming harder and harder to sell you next version.
Some professionals may need it, but most could live with CS6 for a decade (though RAW support for new cameras may force them to upgrade).
In fact when Adobe gets most customers on to this rental model (they may lower the price for some time to do so), they may significantly reduce their software development.
As long as you are locked into file formats, you will have to pay to rent your access to your files (and also to apply your PS skills). They won’t need to add new important features by then like they did have to do in past for each CS release.
I (non-pro) use a GIMP (on Linux), Geeqie (sorting images) and some RAW converters – all free. I have considered LR and PS, but with this kind of software rental I don’t like it. LR is not tied to CC, but it may be in future.
Started out doing photography at the age of 6 using an uncle's old 1940 kodak brownie box camera. At 15 years of age, I decided to buy my very own 1975 Praktica SLR camera. I now shoot with a Nikon D850. I do unpaid TFP and commercial paid work.