Did you know that websites like BPIP, Nintastic, ImgTalk, etc all use plagiarised code? It's legal in the form of "packages", so why shouldn't AI content be legal as well?
The Open Source licenses allow this use, and (usually) allows you to make changes as long as you credit the original writers. By crediting them it's not plagiarism.
In programming things will be a little different.
First, as mentioned, a lot of content can be developed based on Open Source code. Some of this code requires credits to be given, others do not.
Second, the code generated by AI is public code, that is, no one can demand exclusivity. So, in certain cases it will be the same as using public code libraries. It is then up to whoever uses this code to validate, verify and analyze whether everything will be correct and functional. In the end, several details must be evaluated to understand whether or not the script can be considered yours.
One thing is certain, even the code generated by AI does not invalidate not having programming knowledge, otherwise you are exposed to many bugs.
Writing a text, 100% by AI, is something completely different. Because you don't need any specific level of knowledge for everything to "work".