It's already been common-behaviour altering in many ways. I'm not sure if it counts as civilisation altering, but the way we create art, get creative review, find and consume large documents have suddenly changed. Not for the majority yet, but it's only a matter of time. For the first time we can get a knowledgeable ad-hoc assistant anywhere, immediately. Even if it's been bad in many ways, it's improving almost every day.
> the way we create art, get creative review, find and consume large documents have suddenly changed.
I disagree for your first two points. I do use generative AI to create image for my SWADE/DnD campaigns, but this is not art, this is illustration. There is no story behind the style, there is no story behind the color choice, or the meaning of the portraits.
AI was able to imitate Art since at least imagemagik. Kazimir Malevich's art, at least. Music is the same. Unless you think a DJ mixing up without mods or adding anything is an artist, in this case you might consider AI music art. I consider it entertainment.
Never got anything creative from ChatGPT, even when i was paying for it.
Bing chat (and copilot) is great to replace google, scaffold a lot of my code, and definitely boosted my productivity somewhat. But there's a reason why i don't use it to write my scenarii (still use it to spellcheck and syntax check), and even dialogs i have given up on (faster to prepare it myself in the end).
