I think there's a really important point about why Adobe's pissing of it's core cutomer base that people are missing here. All things being equal, it doesn't seem rational for a brand to just piss off it's customers for profit, as it's a bad long-term strategy that will severely damage the brand value/equity.
Perhaps it's because of the implied illegality, but I want to speak to the elephant in the room and offer that simply ignoring the fact that there is a massive market of pirated Adobe Photoshop copies seems to be providing an incomplete picture.
I'm speculating, but willing to posit that the amount of Adobe Photoshop piracy will increase as a result of this decision. Does design major Tim really want to shell out money for the creative cloud to get his weekend project off the ground? I think it's intuitive that this increased piracy would make Adobe less money, but I think the counter is true. They've clearly adopted this strategy because they think they're on to something and any marketing idiot would realize this would piss off their core base, get legit users to pirate, etc. So why would they do it?
Professionals like yourself and myself shelling out money for legitimate Photoshop copies are burdened by the fact that this tremendous amount of piracy exists. Pirates will be pirates, so it's unlikely that you're going to get a pirate to switch their behavior and suddenly gain a new customer; thus I suspect Photoshop's got a finite supply of legitimate photoshop customers, and while it could even be increasing over time it might not be growing at a rate that is in-line with performance expectations (e.g. the adoption curve has hit some inflection point). If Adobe wants to get more money out of Photoshop sales, it's got to look to its existing customer base and find ways of excising more funds overall, and hopefully with more regularity.
I'm not arguing that this piracy isn't effective; indeed, many users are likely legitimate users of Photoshop now exactly because pirated copies made Photoshop training so available despite the high cost for a professional license. I'm not even trying to even make any claims about the ethics involved in piracy.
I'm simply saying that Adobe's business model likely has to look at its adoption rates and its quarterly revenues, and might only see a few options given the reality of the situation. I think this could signal why it doesn't matter that Adobe is pissing off their core base of customers. These customers don't have any viable alternative as you've stressed, so they're locked into the feudalism of Adobe, who's really left with no other monetization strategy other than squeezing out more from existing customers than it can.
