A hobby of mine is editing Wikipedia articles about Australian motorsport (yes, I have an odd hobby, sue me).
The vehicles in the premier domestic auto racing category in Australia, the Supercars Championship, are unique to the category. Like NASCAR, they're built on a dedicated space frame chassis with body panels that look like either a Mustang or a Camaro draped over the top.
I'd seen occasional claims on forums that when the organising body was deciding on the design of the current generation of cars, they considered using the "Group GT3" rules that are used for a bunch of racing series around the world (including the German DTM championship, the GT World Challenge events raced across Europe, Asia, and Australia, and the IMSA GTD and GTD Pro categories). If true, it might be an interesting side note to the article about the Supercars Championship.
So I asked Copilot (the paid model) to find articles in motor sport media about this (there are a number of professional online publications that cover the series extensively). It confidently claimed that yes, indeed, there was some interest in using GT3 cars in the Supercars championship, and pointed me to three articles making this case.
The first was an article featuring quotes from the promoter of the DTM series saying what a good idea it was to have a common car across different national series. So the first article was relevant, but didn't actually show that anyone involved in the administration of the Supercars Championship was interested in the idea.
The second and third references were articles about drivers and teams whose core business is the Supercars championship also running cars in the local GT3 championship (while not explicitly mentioned in the article, they do this for a large wad of cash from the rich hobbyists who co-drive and fund most GT3 racing). Copilot's interpretation of the articles was just flat-out wrong.
Yes, this was a sample size of one historical query, but its response was very poor.