Anthony Joshua has remained tight-lipped since his original June 1 opponent Jarrell Miller tested positive for banned substances.
Miller has received a six-month ban from the WBA after being found to have used performance-enhancing drugs including HGH and EPO.
But despite being excluded from the WBA rankings, he could be free to fight at any time if he is granted a licence.
Joshua says there are plenty of lessons to be learned from the situation - but he slammed the "short" ban handed out.
And he backed calls for severe cases such as Miller's to be dealt with by giving out lifetime bans as boxing looks to solve its growing PED problem.
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Joshua told Boxing Social: "Lesson to be learned - do it the right way. Whether you're taking your exams, your GCSEs, no cheating. Do it the right way, study hard, work hard.
"Good luck to him in his future, I can't knock a man when he's down. I hope he learns from his mistakes and corrects them, and if he does get a chance to fight again he can educate up and coming fighters not to make the mistakes he has.
"It's short, it's very short. Six months if about the time you have out of the ring after a fight for some fighters, looking for the next opportunity.
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"But the WBA have made their decision, they're the governing body, and there's nothing more or you can do about it.
"I don't know how they came up with six months, but that's their decision and we just have to accept it - it's crazy, right?
"Take it case by case, but you should do, yes (give out lifetime bans). When you're man (Miller) is doing the hardcore.
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"I think you've got to take it case by case because not everyone deserves a lifetime ban.
"People do deserve bans and punishment, but when you're doing stuff like that, I think there should be consequences.
"It's like a court of law. If you carry a gun it's one thing. If you actually use it, it's another thing.
"It's case by case but there has to be consequences from the top to bottom."
