People were always able to "instantly use it at the drop of a hat" (paraphrased). What people are objecting to, is instant use without any acknowledgement or attribution (the minimum courtesy). They also object to being mistreated by people who have never actually had to type characters of code into a text-editor, or figure out how to use a build-system and version-control-system. And finally, they object to having their _free_ and _generous_ labor turn millionaires into billionaires (and billionaires into trillionaires), while they themselves still have to pay that one mortgage they have, and medical bills, and tuition, and so on.

They object to the systematized devaluing of their work. They object to becoming a class of invisible laborers (who only become visible when there is need to blame someone).