In a pure debate sense, this would be true, even an unpopular or suspicious person is still capable of making a valid point. It should be considered, however, that internet arguments are not formal debates. They can at times use the form and language of them, but most people are not skilled in that kind of formalized arguing, and most people are not arguing in an actual attempt to use the debate to identify stronger vs inconsistent positions (rather than just trying to push people towards ones own ideas or to put down ideas one finds reprehensible).

Now, I dont personally tend to find much point in looking through profiles, it takes too much time for little benefit in my view, but it can sometimes tell you if an account is not worth the time and emotional investment to interact with, or if it has signs that it might not be. The nature of social media is such that there are always far more user's trying to get your attention, than you have attention to spare. As such, if theres even a notable red-flag that an account isnt worth the time and potential frustration to engage with, it can make pragmatic sense to move on (depending on how much one is willing to put up with, I guess).

From that perspective, telling other people what it was that seemed like a red flag to you lets them consider if that thing makes that account worth their time or not, without them having to find it too, and therefore potentially does those other people a favor. That sounds a bit harsh (at least to me) because plenty of things others might consider suspect, like a new account, cant always be helped (everyone starts off new after all), and being ignored, or having other people call out that thing as a reason they might want to ignore you, is frustrating, but that's just the nature of giving massive numbers of people the ability to talk to everyone else; most people wont want or have the time to listen to you, and you're not entitled to their time, however unfair their reason for dismissing you might be.