They are natural animals, not our property to "train" and enforce our preferences upon...
If you don't like cats hunting birds, don't own a pet cat, as to not sponsor the artificially inflated proliferation of domestic cats.
If you do want a pet cat, respect it.
If you want to own a pet cat, don’t promote irresponsible behavior that intentionally harms the environment. Attempt to have a modicum respect for things that exist outside yourself.
Personal attacks will get you banned here, regardless of how strongly you feel about cats. Would you please review https://news.ycombinator.com/newsguidelines.html and use HN as intended when posting to it?
Indoor cats live longer and don't have problems with parasites, pregnancy, diseases, fights, poisons, predators, cars, stupid humans, or just getting lost.
From the abstract:
"Authors suggested that infection with cat parasite Toxoplasma could be the reason for this association."
From the conclusion:
"Absence of association between toxoplasmosis and depression and five times stronger association of depression with cat scratching than with cat biting suggests that the pathogen responsible for mood disorders in animals-injured subjects is probably not the protozoon Toxoplasma gondii but another organism; possibly the agent of cat-scratched disease – the bacteria Bartonella henselae."
Not exactly a smoking gun.
There are close to a billion people with cats, and like a few tens of thousands suicides, that include tons of people with no cats at all.
Especially since even your article says "Cat biting and toxoplasmosis had no effect on the depression, and the number of cats at home had a negative effect on depression (p = 0.021)."
So, only cat scratching does? As if the people with many cats at home don't get scratch? I wouldn't place much emphasis on a single study of questionable quality (given ample empirical evidence that there's no big deal).
"Cats cause suicides" border on "no vaccines" territory...