They made some more assertions in the second paragraph but didn't offer any support for them so I haven't addressed them separately.

With something like: "Undo support used to be table stakes, but now I'm surprised when it works" —I have to go back to the "two Electrons" I mentioned previously: not sure what world this is where software and business interests have so radically altered as to no longer support e.g. undo. It sounds like they ran into a bug related to undo somewhere and now are weaponizing the fact (as in their first paragraph) as a general argument against the framework.