My answer to the op is the idea is terrible as your own first post demonstrated quite clearly that many first posts in a thread are all you need to read to be able to give a
good answer no matter if it is close to someone else's answer.
The idea's not necessarily bad. It just means the answer depends on the subject matter. If we use this topic for example, literally any member can say the same thing if they feel like it. but imagine it's topic of a Technical Discussion. After the first question and some helpful responses, OP might post another question or the convo could shift gears and simply go in a new direction. Now, its definitely annoying when a new person jumps in and comments without reading the chain of dialogue that got it to that point.