Bluebirds defender Joe Bennett was criticised after a late challenge on Leroy Sane in the game which left the German out for up to six weeks with ankle ligament damage.
The Premier League leaders won 2-0 at the Cardiff City Stadium but boss Pep Guardiola accused the Championship side of putting his players at risk.
Warnock has retorted by claiming that Man City are guilty of making some poor challenges during the campaign but the spotlight had instead focused on his side during the tie on January 28.
"I wish they'd put a still of [Kevin] De Bruyne's tackle [on Jazz Richards]," Warnock told BBC Sport. "And the bad tackle of Fernandinho. And then when they played West Bromwich Albion the following week.
"There were some horrendous tackles and nothing was said because there were another eight or nine games. We were unlucky on the day because Chelsea and Newcastle was the only other game and that was a damp squib."
Cardiff return to Championship action on Friday night with a trip to Millwall.