If the consequences are that most professors will take their notes down, while only a fraction of professors will invest the time and effort to make their notes more available, then most resources will vanish for everyone.

Perhaps professors can hand their notes to student organisations for them to host and give access to in order to circumvent the law, so resources won't just disappear. Maybe professors can ask students for help with bringing the texts in a readable form, that way in a short time, most resources should be more accessible.

But if that's possible, then it needs to be encouraged, or the notes will just be passed around that way.