Indeed. Without the "feudal king" as a unifying factor, Nepal is not even a country. Nepal was never a country before, just a hodge podge of ethnicities.
Only after Prithvi Narayan unified it, then it became a country. If the monarchy is overthrown, there will be bloodbath as people don't see themselves as countrymen, but as enemy nationalities.
"Nepal" will break into hundreds of smaller Racial-States. The Maoists are already doing it by creating "ethnic liberation zones" in western Nepal. The corrupt politicians are fanning it with their backward agenda. And India is financing them both.
there was once a word for that, Balkanization.