Think of it like when you know you need to have the car keys taken from grandpa because he's an actual danger to himself and others.
But it's easier said than done, especially when grandpa is surrounded by people who either refuse to acknowledge his bad driving, or actively encourage him to go out and drive.
Also grandpa is armed and there's no guarantee that any of the people around him will stop him from shooting you and everyone in the neighborhood for trying.
And don't forget that half your siblings are actively cheering grandpa on and calling you slurs for even suggesting something is wrong, and they are also armed and aching for an excuse to shoot you. Your own gun isn't much use since you aren't close to grandpa, and by yourself you can accomplish little to nothing, and you can't reliably call your saner siblings to help out without drawing grandpa's caregivers attention.
The whole government is one giant dementia patient and needs to be burned to the ground so we can build something better, but there's no guarantee any of your siblings will make it or even be successful.
Unrelated, my mental health is great these days.

I got banned from about 15 subreddits I never even knew existed once by calling out a transphobic dogwhistle, and when I inquired about the bans, the mods insinuated I was a child molester and neo-nazi.
Reddit mods don't need to follow any sort of logic.
And confidently asserting someone is a dick because they got banned from a subreddit is hilarious, and should probably prompt some self-reflection.