Incidentally, it's rather common for people with experience on a topic to post shallow dismissals. When a point is obvious from your experience, the only thing that really needs to be said (from your private perspective) is the obvious point. You already have access to your experience and don't need to write it all out.
But it's totally different from the reader's point of view. The rest of us don't have access to your experience, so we need you to fill in the details in order to reach the same conclusion as you. Otherwise the obvious (to you) point comes across as arbitrary and dismissive. It's indistinguishable from a low-value putdown by a commenter who actually doesn't have experience with the topic.
Of course, it takes more time to 'show your work' and walk the reader step by step to the conclusion. But that's what makes the difference between a valuable contribution and a negative one. Comments in the shallow format damage the forum because they encourage people who actually don't know anything to post in the same manner.