No one is saying that. What is being said is to not spread MIS-information. You can do pros and cons of each all day long and that is fine.
Here is an example:
Jacket BCD - Comfy, easy, stylish, secure
BP/W - Comfy, easy, cheaper replacement parts, YOU GET ANTHRAX AND DIE, adjustable,
Well on down the road people get to where they heard their instructor one time say YOU GET ANTHRAX AND DIE and now that has been repeated enough that people take it as truth. A. It is not the truth B. Should not be used as a con for one device and a pro for another.