Operating systems often impose strict limitations on background apps to prevent them from draining resources and negatively impacting the user experience. While you can technically run a node, ensuring it remains reliably connected and functional in the background without being aggressively throttled or killed by the OS for resource management remains a significant challenge for a seamless, "set it and forget it" experience that the average user expects.
Discussion
Doesn't need to be running 24/7. Read the last point of the post.