If you read what the author wrote, he implied that as outside observer he found software engineer eloquent, optimistic and down-to-earth. So he wasn't just reflecting group bias.

I got into software engineer by finding software engineer down-to-earth at least in the sense that it seemed you didn't have to engage in the posturing implicit in finance, say.

That seems to be gone in Silicone Valley but that might be only a small sample of the whole software world.