> It seems like intuitions about copyright have been shifting, even if the law hasn't.

I think people actually know it's wrong and legally questionable.

I believe they do it because they simply want to do it and in the back of their minds, hope adding some bogus disclaimer will let them get away with it... because other people seem to be getting away with it.

I think people think it's legally wrong but not morally wrong, and so they add a bogus disclaimer hoping that they can get away with it because other people have.

At the least, the internet eventually realized that "you must delete your video game ROMs within 24 hours of obtaining them" is not a valid legal stance.

Oh that jogs forgotten memories.

Anyone remember that disclaimer some pirate websites used to have where they said something starting with something like “On October 28, 1998, President Clinton signed into law the Digital Millennium Copyright Act”, and the disclaimer went on to mention some DMCA exceptions like learning and teaching or something? Always gave me a chuckle. As if saying that the DMCA does not apply for you is enough to make it actually so.

No, it's that no one assumes the MIT License is the default one that every open source project ever uses.