Frenchman Takam took Parker to 12 rounds in Auckland last year with the New Zealander winning by unanimous decision. But Takam took the Joshua fight on only 12 days' notice after Kubrat Pulev pulled out with an injury.
"It looked like Joshua was struggling a bit trying to KO him," Parker said. "I fought Takam and afterwards Joshua said 'if I had have fought him I would have knocked him out'.
"He couldn't knock him out [the result was a technical knockout] and I think it was an early stoppage."
Parker said of Takam: "On 12 days' notice he was very impressive - imagine if he'd had a full camp?"
Many among the crowd of 80,000 booed the early stoppage - a testament perhaps to Takam's bravery of fighting in spite of the blood running down his face, and the fact that he was far more competitive than many had given him credit for.
Many of Joshua's fans have also become used to him walking through opponents and this was his first fight since his epic victory against Wladimir Klitschko in Wembley in April.
Ref Edwards moved in after a cleanly thrown hook from Joshua, who followed up with several shots which missed their target. Takam was steady on his feet and defending himself and outraged at the official's decision.
While Joshua, 28, wasn't hurt by Takam, he was taken outside his comfort zone - and not only due to that nose injury. Takam, chin tucked behind his left shoulder, wasn't as defensive as many thought he would be.
He was aggressive in the middle rounds and caught Joshua to the body time and again - shots that may have contrived to slow the big Englishman down.
Certainly, Parker believed that was the case, the 25-year-old believed the fight would have gone the distance but for Edwards' intervention.
"I've said it many times. I'd love to fight Joshua so I can show what I've got. He's good - he's big, strong and learning, but I think he's just average, he's robotic. The jab he was throwing was very slow. He steps up all the time but I don't think he looked that impressive today.
"There wasn't a lot of movement. He stood on the spot or tried to chase Takam down and catch him with big shots."
Joshua entered the ring weighing 115.6kg - his heaviest ever. Many observers, including Parker, believe that may have been the reason behind Joshua's sluggish and heavy breathing in the latter stages.
Parker weighed in at 112kg for his recent points victory against Hughie Fury in Manchester. "Even for myself, I find if I'm heavier I don't move as well. I'm trying to get down to 238 or 239 pounds [108kg]."
In the Principality Stadium ring afterwards, Joshua's promoter Eddie Hearn said Parker was a potential opponent for Joshua next year, along with WBC champion Deontay Wilder. But as the Kiwi said, it's all about the offer Hearn and Joshua are prepared to make.
