I'd say "-site:reddit.com" helps a lot. And also "-site:youtube.com" and some others :)

Admittedly, I usually do the exclusion in my brain and not actually via the search query.

I don't know where the hype comes from, which says that reddit posts are particularly smart and useful. Maybe just from their own marketing, which is repeated over and over in social media by these 'smart' guys?! It's completely not reflected by my practical experiences at all.

When I accidentally end on a reddit thread and read some posts, I'm always like "Well, and that's it? What a waste of time..."