Warnock came under fire earlier this week after footage emerged of him appearing to give referee Stephen Martin a hard time after his side's 3-2 defeat to QPR
The former Leeds, Crystal Palace, and Cardiff manager felt aggrieved that QPR striker Charlie Austin wasn't sent off for a headbutt on his player, Dael Fry.
But Cassidy insists that Warnock going on to the pitch and shouting at the officials is counter-productive, and is worried that young players and managers will imitate the 72-year-old if they see him on television.
"This isn't about Neil Warnock per se, it's about the behaviour that he thinks is acceptable that then gets replicated at lower levels," said Cassidy.
"Just like a Cruyff turn from years ago, just like a Cristiano Ronaldo goal celebration, just like wearing your socks as Jack Grealish does, they all get mimicked.
"All of the things kids see on TV get mimicked, so it would be stupid to say the behaviour Neil Warnock displays wouldn't get mimicked too.
"I said on TV on Tuesday that I believe the Football Association won't do anything until the referee is murdered. I'm not saying that going to be because of Neil Warnock but it's like a snowball.
"I think Neil does bring something to the game that needs to be admired, without a shadow of a doubt.
"I just think he spoils it time and time again. If there was anyone who you're going to put money on doing these pantomime acts, you would have put it on him or Jose Mourinho.
"Why did he always think referees are fair game post-match. Why does Neil think it's acceptable to do that?"
Warnock then had his chance to respond and questions the ability of some of the referees in the EFL.
"I don't accept that," Warnock argued. "I'm not sure I respect Martin Cassidy Group either if I'm honest."
"Not when I listen to what they say, when they talk, I think sometimes I don't agree with their comments.
"You'll never get referees like in rugby where they're wired up and listen to everything. Because if you heard what they said it would cause embarrassment.
"I didn't even have a go at the referee against Chelsea (when he was Cardiff manager in 2019).
"I'd gone on to thank all the fans which were fantastic, and I go round all four corners of the Middlesbrough ground as well to thank them after the game. You can't just change things like that.
"I know you've got to jump on something but I think I'm an easy target if I'm honest because most of the managers now have clipboards on the bench. Mikel Arteta must be your dream, Martin!
"The referee said to me that he thought it was accidental. He saw it. That's what we're up against. Who teaches these people?
"He said to me, and I'm repeating, 'I had a good view of the incident and I thought it was an accidental clash.'
"I said to him that when he sees the video, he might change his mind.
"I spent an hour yesterday writing the report and, in about a week's time, I will get a reply from the Referees' Association saying, 'Yes, I'm sorry the two offsides shouldn't have been given. Yes, it was a good tackle. Yes, it should have been a red card to Charlie Austin.'
"That's no good to me in a week's time is it?"