I see what you mean. I'll try to give an example.

I tend to be skeptical of folks when I know they're incentivized monetarily, emotionally, or socially to believe a certain thing but I do my best not to discount them out of hand. I think most people have a tendency to write folks off completely when it's more useful to accept uncertainty. To know that a piece of information might be right even if it challenges my worldview. Unfortunately uncertainty is kinda hard work.

For instance, the US has a lot of incentive to make alternative economic systems seem awful. Anytime a pro US media source like Radio Free Asia says something negative about China. I have to accept that:

1. They've lied in the past
2. They're incentived to lie again
3. It's still possible they're telling the truth

I have to accept that balance.

This works well for situations that don't effect me personally. On the other hand, if there's a person who has a predatory reputation in my friend group, I don't have the luxury of giving them the benefit of the doubt. They are a present danger to myself and the people around me.

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.