Graphene shills have been banging on this point for donkey’s ages. Reality is that many people use phones that are out of OEM support and many OEM ROMs are bundled with questionable software (Oppo, Samsung etc.) There are some decent criticisms to be made about LineageOS, but others to be made about Grapheme, like its Google-suggestive configurations, which is quite bad for security and privacy. Graphene says this is all optional and not part of the OS, but doesn’t include any equivalent F-Droid installer.
Really good points. I like that the concept is saleable both as a reliability improvement for trains and a safety and capacity improvement for the road network (which can also include buses). Everyone’s a winner.