I know nothing about BrandonM but I envisioned him as a highly technical person that knows what he is talking about.
He still couldn't evaluate whether an idea will be successful in the market. That's why Paul Graham in the OP admits he thought Airbnb was dumb idea. Then says not to speculate on what people want but to build something for yourself.
BrandonM doesn’t mind:
> I really don’t mind the commentary. I’m long past being frustrated about being misinterpreted, and I learned a lot from it, anyway.
https://news.ycombinator.com/item?id=27070138
But dang does:
> my heart sinks a little every time I see this brought up
https://news.ycombinator.com/item?id=27067281
It’s thoughtful context that I think everyone mentioning BrandonM and Dropbox should be familiar with.