I recall reading that ~30% of humans have evidence of toxoplasmosis. But, it is unclear whether that is harming their intelligence. Statistically, cat owners have higher IQ than dog owners (pls do not shoot the messenger unless you want to provide further evidence of the validity of this observation).

I’m a dog person, but most cats are lower maintenance than most dogs.

> so little in return.

That's simply not true. You clearly never had a cat.