Well, again, just for fun. This is by no means scientific, but we have some historical examples of when monarchy was disposed of. One of them is England. It can be argued that that hiccup in orderly transfer of power led to the United States of America, or at the very least, enabled it.

More recently it was Russia. The Russian monarchy was overbearing and inefficient. But under it Russia experienced something that might be called technical and economic progress. Under the Soviets. Stalin was more powerful and malicious than any Russian royal ever (Ivan the Terrible never had that kind of power over the entire territory). Similar examples can be found in China, (North) Korea, and of course, Germany.

Reminds me of one of the cleverer scenes in "Game of Thrones"