This is truly one of the best moderated places on the internet IMO, and one of the only places after 20 years of posting on message boards that I can go without hurtling toward a flame war every time I log on nowadays. Part of it is, I'm opinionated and I think probably enjoy arguing more than might be reasonable sometimes. Another part though is that the moderation quality is so high here and so low on places like Reddit + Twitter. My 2 pence.
Probably the lack of ability to advertise here the way you are encouraged to do on Twitter/FB/IG/Reddit (because they need that revenue) factors in as well.