I don't agree with laughing at these things. It's a fine line between calling something hysteria and suffering from hubris. The Titanic is a completely inverse case of hysteria. They were so damn confident it could work that it didn't work at all. So yea, just laughing at dumb people isn't a valid argument to dismiss doubts.

On the other hand some kinds of hysteria occurs due to a divide between the public and subject matter experts on topics. Kind of like Dunning Kruger. Take for example the people saying 5G causes cancer. Then there are people who blanket dismiss their worries, because "it's non ionizing you dummy". Given sufficient power you can still fry someone with non ionizing radiation, for example in radio broadcasts. Of course a regular 5g antenna can't put out that kind of power but my point is that people too quickly raise or dismiss concerns without actually critically examining the entire topic. This will likely worsen from specialization and progress in all fields and regular Joes get left further and further behind.