If people were using inductive reasoning, that would be fine. They aren't - as I said they're trying to eat the cake and have it too: "expert said so, then it's true/false lol lmao".

And in the process they rush towards certainty on things that might be completely false, often because they're being manipulated to do so - because it's trivially easy to claim authority over a subject, or to stain someone else's authority over it.

Just saying maybe your expectations are too high for a public Web forum.

My expectations - not just for web forums, but also for real life - is that, when we don't know something, we shouldn't claim that it's true or false. It's fine to conjecture, it's fine to say what you think/guess, but not to make a hard statement, unless you have good grounds to do so.

And inductive reasoning does not give you those good grounds to claim certainty.

However, I think that in web forums this rubs your typical user the wrong way. They want to believe that they know something, but aren't willing to spend the necessary effort to do so.