What survival myth is completely wrong and can get you killed?

https://lemdro.id/post/37509347

Boiling water for safety.

No, you are only concentrating the heavy metals, neurotoxins and the salt in the water.

You need way more context about what you are trying to eliminate from your water to do it safely.

That is dumbest post I have read this year. Congratulaton.
The dumbest post this year, so far.
That we know of