But former England opener Moxon agreed “drastic” action had to be taken in the wake of the ball-tampering scandal, which has overshadowed the current Test series in South Africa.
Australia captain Steve Smith and deputy David Warner were given one-year bans by Cricket Australia, while Cameron Bancroft was suspended for nine months for his part in the incident.
Lehmann was cleared of any wrongdoing, but last week announced his decision to step down after the fourth and final Test, which started in Johannesburg on Friday.
“The public were obviously outraged by what they saw,” said Moxon. “It’s tough for those three players in particular and Darren Lehmann, obviously a good friend of mine. We go back a long way. To see him so upset and a part of this, it’s tough for those guys.”
Moxon worked with Lehmann for three years during his first spell as Yorkshire coach after the Australian had arrived as the county’s overseas player in 1997.
“Only he could make the decision,” Moxon said. “But if he had no part to play in what happened, it’s terribly sad for him to have to finish his career with Australian cricket on these terms.
“Clearly he thought enough was enough and the abuse he was getting and his family was getting, he felt it wasn’t worth carrying on, which is very sad.
“I do feel for him because he’s a good man. He plays cricket hard, but in the right spirit and that’s how I’ve always ever known him.
“He likes cricket to be played with a smile on your face. It’s to be enjoyed, in his mind, as far as I know him.”
Moxon said the outrage which followed the ball-tampering during the third Test in Cape Town was understandable.
“When you saw it on TV you had to kind of double-take at what was going on,” he said. “I think it was just the blatant disregard for the rules, that was the most surprising thing.
“From a distance, and I haven’t been anywhere near the Australia camp, it smacks of a ‘we can do what we want’ kind of attitude. From a distance, it appears that way.
“They’ve shown genuine remorse and it’s sad to see them in such a state on TV and in public.
“To see them in that condition is upsetting. I’ll be honest, I was surprised at the Australian public’s reaction.
“How hard they were on their own players was quite telling really and clearly Cricket Australia had to do something drastic as a consequence of that.
“You can argue whether it should have been six or 12-month bans, but that now sets the precedent going forward.
“People know that if they’re going to go to those lengths, the consequences are going to be pretty dire. Hopefully it will stop it.”