You aren't getting any push back, you are simply getting explanations about something that is completely unnecessary and I already told you that you can use the scan for added / removed roms tool that is available.
You are using Plex and EmulationStation as examples but those are very specific needs programs, they both know exactly what files are used by the system in place. In the case of Plex it knows to look for specific video files and in the case of EmulationStation it is using Libretro cores and again knows specifically what file types it needs. Launchbox is far more open ended and leaves all of that to the end user because different users use different emulators which of course have their own unique way of handling different files.
And just for the record, both myself and Dos76 are paying customers as well, we are not paid employees here.