I agree with some parts but I mostly don't see the point of this article: shooting down ideas is a skill in academia, in industry, in fields where decisions have huge opportunity costs. One needs to shoot down ideas pretty often, because really good ideas are only a handful.

Things that are really worth someone's time are often something that should be well thought out, stress-tested, collectively agreed upon by at least a few. So shoot the unfeasible ones bang on so you don't waste time on it. Just don't make it personal; it's only ideas that need judgement, not the people.