While being used correctly, AI can surely assist the restoration process. However, for many of the cases, studios just do a whole AI upscaling pass, and leaving all kinds of weird artifacts and smoothing.

Some serious offenders include:

• Alpha Omega Digital from Germany, which has the worst offender of the bunch in Twenty-Four Dollar Island https://slow.pics/c/dFdgCFgn?image-fit=contain making the 1927 film look like a cartoon. It also did restoration and Aguirre and Nosferatu the Vampyre, and supplied them to BFI 4K, causing a big blow-up on reddit

• Paramount's I Love Lucy also has this ghastly AI restoration that's applied to almost all of its collection even including extras, even though the source is 35mm, rare for a TV show. It had to issue replacement discs later due to the pressures, but that only replaced one episode.

• James Cameron very famously not only likes AI, but also personally likes extensive DNR, motion smoothing, and AI upscaling, so most of his home video release are "ruined" in one way or another.

• Hanselab has been using AI upscaling for many of their releases, like Diabolique (1996), The Crush (1993), and Renegades (1989).

Thanks nemwolf for contributing to this list