That sounds about right. Lots of abuses have been perpetrated by opportunists, charlatans, fraudsters all for money, as you put it. I just want to make sure we correctly distinguish what is meant by "opportunists, charlatans, fraudsters."

In the spirit of full transparency, I've listed some of the most well-known cases. Others, due to the Iron Curtain and similar curtains are hard to document, due to lack of visual inspection. Just the same I've listed them for transparency's sake:

Western Bloc:

Tuskegee Syphilis Study (US, 1932–1972)

Project MKUltra (US/CIA, 1953–1973) Human radiation experiments (US, 1940s–1970s)

Porton Down nerve/chemical tests (UK, 1950s–1960s)

Ewen Cameron brainwashing/LSD experiments (Canada, 1950s–1960s)

Eastern Bloc:

Soviet Gulag prisoner chemical/medical experiments (USSR, 1930s–1950s)

Punitive psychiatry experiments on dissidents (USSR, 1950s–1980s)

Pre-1940s Germany:

Nazi eugenics forced sterilizations (1933 Hereditary Health Law; ~400,000 citizens)

Pre-1940s Japan:

Unit 731 biological/chemical experiments (est. 1936; pathogen injections, early vivisections on prisoners)

Axis Powers:

Nazi Germany: concentration camp medical experiments (Dachau/Auschwitz hypothermia, twins, sterilization; mainly 1941–1945)

Imperial Japan: Unit 731 & affiliates (vivisections, plague/anthrax tests; ~3,000+ direct deaths, 200k+ from field use)

Fascist Italy: No major documented equivalent programs

Asia:

Japanese-occupied territories (China, Manchuria, Korea, etc.): Unit 731 satellites (biological warfare tests on local citizens/POWs)

By the way, all the above instances are part of history.

Greed is greed, whether "Capitalist, Socialist or Communist-oriented." In my view there is no distinction between modern day and historic "opportunists, charlatans, and fraudsters." Greed is Greed!