I find it amusing that wars and turmoil are totally cool as long as "DER RIGHTFUL HEIR!" takes the throne afterwards.
Meanwhile a month or two of having a temporary government before electing a new one (or in case of simply removal/death of a president, having the vice-president or equivalent rule instead) is somehow proof that democracy doesn't work.
Really, have you ever seen politicians die during their term or get kicked out? Because both have happened in Finland. Heck, Kekkonen dying was no problem for democracy at all (long story) and several parliament members have been kicked out from their job and replaced due to corruption or shenanigans.
But when you do that to a king the line of succession breaks. Even the best case scenario is proof that inherited position of king has failed. If the king had been from a "better" line or if they had divine mandate then why did someone like that get the position? And if they are no better than the average mortal then why should their kids get to be the next rulers? At least the Swedish kings of old were elected democratically (yeah, they were basically a "president for life" in all but name) and until one of them decided to make his son the next king and take away democracy for a few centuries they really had the best way to handle monarchy the planet has seen. ...And even then term limits that democracy (usually) has is an even better improvement on that.