Are toilets harmful (for health, wealth and marriage)?
The toilet in ancient China was a dirty place. Microbes thrived here and caused health problems. When someone got sick, money had to be spent, and many opportunities to make money were missed. This also adversely affected the relationship between family members, in particular between husband and wife. Thus, the toilet had to be located in some remote place.
In modern homes, as long as you empty the cistern and keep everything clean and hygienic, toilets don't do any harm.
Some of the ancient principles of Feng Shui need to be revisited. Learning that flushing the cistern takes away wealth is irresponsible behavior.