The reason one should be careful of who they listen to (even when listening with a critical mind) is groupthink. Here's what happens when you listen to someone:

- You agree with the things you have reason to agree with

- You disagree with the things you have reason to disagree with

- Everything else they say gets an uptick of social proof

There a bunch of stuff that you're totally ignorant about, and you have just absorbed a tiny bit of this guy's opinions about it. The stuff you know is safe, but the stuff you don't know is polluted.

I try to pretty actively prune the communities I pay attention to. I have serious misgivings about spending so much time on Hacker News. I'm relatively ignorant about business: there are things I don't even know that I don't know about. And on Hacker News I'm getting a bunch of brainwashing on those topics without being able to critically evaluate it. With respect to those things I'd be better off hashing stuff out on my own like a pre-school toddler, building up lived experience with which I can evaluate what people are saying.

But on the other hand, I learn lots of cool tricks here, so I've decided it's worth the risk.

And personally, I decided it was worth the risk to look at what Barr has to say. But I think the risk is clear and present.