My understanding is that GOG is an exception to this. Here is a quote that I got from an Ars Technica article

California’s AB2426 law, signed by Gov. Gavin Newsom Sept. 26, excludes subscription-only services, free games, and digital goods that offer “permanent offline download to an external storage source to be used without a connection to the internet.” Otherwise, sellers of digital goods cannot use the terms “buy, purchase,” or related terms that would “confer an unrestricted ownership interest in the digital good.” And they must explain, conspicuously, in plain language, that “the digital good is a license” and link to terms and conditions.

Since GOG does offer permanent offline installers that can be used without an internet connection, GOG’s sales are exempt from this new law.