I've always lived in walkable cities. I don't own a car and with pollution, congestion, accident risk, pavement obstruction, etc. other people's cars unequivocally make my life worse.
We can argue about whether this is a good trade off, but the claim that cars make everyone's life better is straightforwardly false.
Troll post? No, they do not "unequivocally" make your life worse. "Other people's cars" facilitate thousands of aspects of modern living and society that you apparently take for granted. You can choose to ONLY look at the negative impacts, but the comment as stated is ridiculous.
The only way you receive food (except from your backyard inner-city garden?) is through people DRIVING. The way you receive packages is by DRIVING. They city infrastructure you enjoy is maintained through skilled laborers and tradespeople DRIVING.
I live in a walkable city. I cannot drive because I am blind. Cars make my life better. Uber exists. I use it to get many places that I otherwise wouldn't go to.