I think the old saying is that you are a combination of the 5 people closest to you. I'd take that a step further by adding that your mood is also a combination of the things you consume and surround yourself with. Sadly, doomer vibes tend to be stickier than optimistic ones.

Exactly. That is a warning not just a pithy quote. Book authors, podcasters, youtubers, nostr posters and any other content consumption all pulls on that average.