Used to act; not so much any more. Perhaps kings is history acted that way, but I really can't envisage the monarchs of Andorra, Belgium, Denmark, Luxembourg, the Netherlands, Norway, Spain, and Sweden behaving as Trump does, and it's clear that King Charles doesn't. Perhaps in the Middle East: Brunei, Oman and Saudi Arabia, the United Arab Emirates, Qatar, Bahrain, Jordan, Kuwait, Malaysia and Morocco might get away with it (in a limited manner, though Saudi is more autocratic than most). Bhutan, Cambodia, Japan, and Thailand have very much ceremonial monarchies without the power to Trump about; I have feeling the only absolute monarch left around is the Pope, and technically he isn't a king anyway.
Dictators, now, dictators behave like Trump....