Because it would be absurd for it to be legal to do X, but illegal to do so with an efficient tool. Especially when the activity X in question is "learning".
No such thing, "learning" in a vacuum describes nothing here. Might as well ask why I am allowed to make noise, e.g. speak, but when I install 5000 watt speakers on every square meter of the planet suddenly it's a problem, and roll my eyes at the inconsistency of not being allowed to "do X more efficiently with a tool".
Did we somehow stealthily develop a neural interface that lets us feed the 'learning' that 'AI' is doing into a human brain? Have we actually figured out how to do that?
No, we haven't. So humans are still learning the same way, but with a new tool to condense and summarize some information. Kinda like a textbook in school. But we don't treat those as human beings with human rights do we?
It's legal in most places in the U.S. to own a semi-automatic weapon that fires x bullets/minute, but not a fully-automatic one that fires 10*x bullets/minute. It's legal for me to send water into my sewer by flushing the toilet, but not for me to pump the larger volume of water in my sump pump into that same sewer.
It's legal for a child to throw a handful of sand from the beach into the ocean. Do you think it should be legal for anyone to build and operate a sand throwing machine that methodically throws all of the sand on the beach into the ocean?
We've been living in a world where people read news articles, then wrote almost the same article on their own website to sell ads. It's been a standard business practice for a decade now, what's so special about LLM based blogspam? The end impact is still the same, people reading the blogspam instead of the source
I'm going to bypass this question a bit and say, who cares?
Why do we need to treat these things the same way we treat humans? Why can we not say that it's okay if a human does it, and not okay if it's a computer? There's nothing that requires us to establish 'fair' as treating them the same as people.