At some point, software vendors are going to need to address the issue that when they make crappy updates, people don't apply them.
Consider mobile app store updates: they rarely install other unrelated crapware, don't reconfigure your device settings, and don't require reboots... and users typically install them automatically. Conversely, Apple's PC software updates typically do all of the above, and people regularly decline them as a result.
Hence it's not a problem with update fatigue, it's just a problem with companies producing crappy updates, and users getting conditioned to expect (and decline) crap from certain vendors.
Here's hoping Apple et all get sued at some point for this, and/or something else happens to motivate some improvements to the update process. There's no reason people shouldn't be running updated software, aside from laziness and/or incompetence on the part of the vendors.