Yes, IIRC the “Unforgivable Curses” either carry a death penalty or wizard prison forever or something. But by the third or forth book every bad guy is a Wizard Nazi who doesn’t care about those consequences and the good guys are all fighting Wizard Nazis and are at least semi-justified in trying to kill them right back.
It basically devolves instantly into gun-fights, except instead of guns it’s a specific spell.











Germ theory was controversial when we didn’t have microscopes that could see microbes. Terrain theory is working backwards, that germs are attracted to areas of disease. It is so trivially easy to disprove today that it was disproven in 1870.
Doctors do not use “Germ Theory” to diagnose patients. Research into chronic and/or viral diseases has not stopped because “it’s probably germs”. Treating germ theory as the sole monolith of modern medicine is petulant contrarian nonsense that is grouped in with a whole host of other anti-establishment conspiracy theories.