I see the picture:
https://nitter.net/pic/orig/media%2FHPbcUXaaEAANwEa.jpg
She must have used some sort of filter or effect that made it look like Ai, this background in particular:
https://www.mangago.me/read-manga/the_melting_season/uu/br_chapter-414832/pg-25/
It might not be Ai generated, but it might be Ai edited based on the way the details get merged into one another
Look closely at this one: https://www.mangago.me/read-manga/the_melting_season/uu/br_chapter-414832/pg-25/
Yes, that is the image I was referencing, once again, it looks like any basic background you'd see in a comic like 19 Days. I do see what youre talking about like the Olympic rings smudging, but I honestly think thats their use of atmospheric perspective, or whatever its called when you draw less detail to depict distance. This is way more evidence than the other person making the claim, so I thank you for that though, however I still don't think it's substancial enough when thats a legitimate art technique.

Come on, this was just a good read only for it to have AI backgrounds
I cry T-T