I think you did alright by resorting to flatpak. When it comes to closed source applications, it's not uncommon for problems like this to appear every so often.
The problem here is that we are dealing in largely imprecise terms. If we instead turn to semantic versioning for inspiring what we'd consider a large change, then Plasma 5 -> 6 is a big change, breaking previous API.
The new desktop edit effect is largely irrelevant under this rather precise terminology.
I don't think anyone has misunderstood you here. You misunderstood what you wrote in your first comment. The new desktop edit window is not proposing any new functionality that wasn't there, but showcasing it in a more streamlined fashion. That's in itself refining the user experience, which is exactly what you wanted.
The ultimate litmus test for knowing if a south American country is a democracy or not - does an English speaking lad want to overthrow its government? If that is the case, chances are high it is a democracy...
Also Darwin Núñez played a match about the same time frame, so funnily enough those two comments must have overlapped