Maybe because this is something very close to my wheelhouse, but this article seems to be overly wordy for something obvious. Smartphones are simply more convenient than a standalone camera can ever be. Add on top of that the incredible computational imaging capabilities that have been developed over the past few years and the quality of images you can get from the size of optics and pixels that these devices have is…
Camera companies are user hostile and the people buy them are used to it. Terribly menus and interfaces, and they don't even care. Even their key features, like video recording are reduced to a 29 minute limit due to an old expired regulation (hello Sony A7iii). USB-C ports for data transfer that can't be used for charging. The list goes on.
That's not entirely true. The usual excuse is that transcoding generates significant heat and without sufficient cooling the cameras will be damaged. To some extent this is true.
It tends to depend on the bitrate; 4k will get hotter faster than 1080, and 480 will go for long enough to not be a problem generally.
If you stream to an external transcoder/recorder, you can typically record indefinitely with most modern bodies.