I currently use a 2008 Fujifilm camera and a 2018 Sony. The Fujifilm doesn’t even have a firmware update mechanism, and the Sony camera doesn’t get updated anymore. These devices are rarely connected to the internet and never go obsolete so they get used until they break.

There might be a specialised line of cameras for forensics that signs the output and has lidar to detect when the camera is pointed at a screen, but the average person won’t have a camera with this kind of crypto. It would just be too easy for hackers to extract the keys from.