Shadow Tag is probably the most controversial ability in the game, and given that it's obtainable by a Pokemon with so much strength and potential, I don't see why you're so surprised that people want to weigh in their thoughts on it.
The problem with people weighing in their thoughts is that most of them are the same thoughts already expressed, just rehashed and repeated on and on for pages. The thoughts aren't often particularly well formed beyond the "145 SpAtk + Shadow tag + hypothetical scenario which demonstrates power = BROKEN" stage, either. And then people who want to counter those thoughts have to post, and then it all repeats and doesn't go anywhere.
Admittedly, it's hard to go beyond that because unless you're pokesaving you don't have shadow tag shandera, but there are still things we can do beyond repeating the same superficial arguments for why we should fear shadow tag shandera over and over again. For example, we could analyse the youtube battles in which shandera is used and discuss how the battler could have better utilized shandera, because right now most people suck at using it. We could present calculations for damage shandera can do to various threats to it/good targets. We could combine this list with data from the speed tier thread to see what scarf ST shandera looks like it could reasonably threaten well, etc.
If you can't get any discussion going about Flash Fire then that's kind of your fault for not saying anything interesting.
Even a decent quality signal can be pretty hard to pick up in the midst of too much noise.