Earlier quoted context omitted.
I think the GP hit the nail on the head with the phrasing "anyone who uses jargon unnecessarily ". Jargon is meant to make communication clearer and faster between peers. If it is making it less clear instead, there is something very wrong.
I once worked at a company that had so much jargon they published a glossary on their Sharepoint site, and a list of TLA's (Including 'TLA' itself as the joke goes...it means 'Three Letter Acronym' for the uninitiated. This is what I might call, 'treating the symptom of bad communication and not the cause'.
One company I was at had a jar in each conference room. When you used an internal name or acronym without first defining it, you had to put a $1 in the acronym jar. This was used to buy the team lunch. They had to abolish the policy as it was seen illegal to force such behavior. It worked very well while it lasted though.