You were downvoted because, whether or not they understand the numbers or know the names, most people understand that long lived bioaccumulative high activity a

You were downvoted because, whether or not they understand the numbers or know the names, most people understand that long lived bioaccumulative high activity alpha emitters like Tc99, Cs137 or Pu240 are really, really bad. Obvious half truths and misdirections told in a really arrogant way then re-enforce the idea that anyone telling them any amount of radiation is safe is deliberately trying to mislead them, and so they wind up trusting nobody. They then correctly infer that the liar is malicious and trying to scam them. So all in all they get to the right place even if it is for the wrong reasons.