That many people who are criticizing Microsoft for using open source code and claiming “fair use” and saying it’s not fair to creators are the same ones that say pirating digital content is harmless.
Because issues aren't automatically symmetrical, and impact of actions isn't equal in both ways, especially when there's power difference between the sides of the conflict, e.g. it's not hypocritical to punish a bully punching their victim, but not the victim for punching the bully back.
Disney used its power to distort copyright laws in a self-serving manner. As an individual you don't have equal power to oppose them (you were supposed to have in a democracy, but lobbying is legal and corporations are people).
Disney is a huge corporation that won't even notice if you pirate a movie, which you may not even have been able to pay for anyway, because of their region-locked twisted maze of distribution and DRM.
OTOH you may be screwed if you're a creator making a living from your work, and a big corp can just take it without paying, launder it through "… in the style of $YOURNAME" query, and say they own it now, because unlike your copyright, their Terms Of Service apply.
Even people who think copyright shouldn't exist may rely on using copyright — against itself. You can't unilaterally say "I don't believe in copyright", because the law doesn't care, but if you license something as copyleft, then the law does care about your anti-copyright license.
