What happened is that Adobe pirated someone else's software - specifically, Dolby's. They slathered surround-sound support into all their apps, but used very questionable accounting methods to avoid paying for all that licensing. For example, if they added 5.1 support to Premiere, they'd only count it as a "sale" if you actually opened Premiere and used that particular feature. This is a blatant license violation.
Creative Cloud used to have a feature where you could install old versions of their software, all the way back to CS6. Of course, if Dolby's lawsuit worked out, each version you installed could count as a separate license violation. Hence, they took away that very generous old version support and said you only get the latest version and last year's version.
As one of the developers for Ruffle, this absolutely sucks, because there is no Adobe-sanctioned way to generate test Flash movies with ActionScript 2 code anymore. That support was removed when they released the first Creative Cloud version of Flash, which is already many years old and also not provided by Adobe anymore.
I wouldn't say 'blatant'. That seems like a reasonable tactic in a vacuum.
I guess they could have made it a separate download and install when you click that menu option, but the end result would be the same.
But if you look at what actually happens to the IP, there's a good argument that dolby has no right to any payment from a user that never touches their IP.