If you run someone's artwork through a filter is it completely fine and new just because the output is not exactly like the input and it deletes the input after it's done processing?
No, that's a derivative work. An analysis of the brightness of the pixels is not a derivative work.
There is a discussion to be made, in good faith, of where the line lies, what ought to be the rights of the audience and what ought to be the rights of the artists, and what ought to be the rights of platforms, and what ought to be the limits of AI.
Sure, but the people crying "You're stealing art!" are not making a good faith argument. They're using an inaccurate, prejudicial word for the purpose of riling up an emotional response. Or perhaps they just don't understand what copyright is and why it is, which also puts their argument in a bad state.
The reason why Copyright even exists, at least ideally, is so that the rights and livelihood of artists is protected and they are incentivized to continue creating.
Case in point. That's not why copyright exists. The reason for the American version of copyright is established right in the constitution: "To promote the progress of science and useful arts". If you want to go more fundamental than just what the US is up to, the original Statute of Anne was titled "An Act for the Encouragement of Learning".
The purpose of copyright is not to protect the rights or livelihood of artists. The protection of the rights and livelihood of artist is a means to the actual purpose of copyright, which is to enrich the public domain by prompting artists to be productive and to publish their works.
An artist that opposes AIs like these is now actively hindering the enrichment of the public domain.