alt Hacker NewsOr maybe it's inherent to power and the recent trend is against human nature. You cannot seriously say that this is a major concern in moving against monarchies. After all, the royals are just the most well known ones (because it involves succession). Plenty of non royal powerful people also do so.
People have always been ostracized for adultery, royalty or no. You need only look at stories from e.g. the Old Testament or similar to see how long this has been a thing in human society.