As so often, the claims are a bit of a joke...
The Papyrus Westcar - Berlin Papyrus 3033 (AKA “Three Tales of Wonder from the Court of King Khufu") is from ca. 1600 BC, and thus "only" 3600 years old. It contains 5 stories about Pharaos of the Old Kingdom. The alleged barb is referring to the following story:
Then Bauefre stood up to speak, and said: “I will let your majesty hear a wonder which happened in the time of your forefather Sneferu,justified, and is something that the chief lector priest Djadjamankh did”. Then he told the story of the green jewel.
[ ] day things have not happened. [Snefru went through] every room of the palace to seek distraction for himself but he couldn’t find any. The he said “go and bring me the chief lector priest and book scribe Djadjamankh and he was brought to him immediately. Then his majesty said to him “I have gone through every room of the palace to find distraction for myself but I couldn’t find any.”
Then Djadjamankh said to him “Oh, may your Majesty go to the lake of the palace, and man a ship with all beautiful women from inside your palace. The heart of your majesty will be cheered by seeing them row a trip back and forth and seeing the beautiful reeds of your lake and seeing its beautiful fields and water banks. Your heart will be gladdened by this so I will arrange a rowing trip.”
Let there be brought to me twenty oars of ebony plated with gold, their handles of sandalwood plated with electrum. Let there be brought to me twenty women with beautiful bodies, well developed breasts, who have braided, and who have not yet given birth. And let me be brought to me twenty nets and give these nets to these women after their clothes have been taken off”. All was done as his majesty commanded. Then they rowed back and forth and the heart of his majesty was gladdened by seeing them row.
Then one woman who was at the stroke oar got entangled in her braids and a fish pendant of real turquoise fell in the water. Then she became still, without rowing and her side became still, without rowing and his majesty said “can you not row?” and they said “our stroke has become still without rowing” and his majesty said to her “why are you not rowing?” and she said “this fish pendant of real turquoise has fallen into the water” then [he said] to [her] “[it shall be] replaced” and she said to him ” prefer the real one to a substitute” and then his majesty said “go and bring me the chief lector priest Djadjamankh and he was brought immediately.
Then his Majesty said “Djadjamankh, my brother, I have done what you said any the heart of his majesty was gladdened by seeing them row. Then a fish pendant of real turquoise on one of the strokes fell into the water and she became still without rowing. It so happened that she disrupted her side and I said to her “why are you not rowing” and she said to me “the fish pendant that was real turquoise has fallen into the water” and I said to her “Row, lo I myself will replace it” and she said to me “I prefer my own thing to its substitute”
Then the chief lector priest Djadjamankh spoke a spell and put one side of the weater of the lake on top of the other and found the fish pendant lying on a shard. He fetched it and gave it to its owner. Now the water was twelve cubits in the middle and it ended up being twenty-four cubits after being folded up. The he spoke a spell and the parts of the water of the lake returned to their positions. His majesty spent a day of celebration with the entire royal household and at the end he rewarded the chief lector priest Djadjamankh with every good thing.
The girls are not wrapped in fishing nets - they were given them to fish. Now, women in Ancient Egypt usually did not run around without clothes outside, but fishing was done in the nude. No doubt, Snofru just used this as an excuse to see the ladies in their natural state, but there is no hint of criticism, and the point of the whole story is to extol the good services of Djadjamankh.
[Edit] Some scholars think that not real nets, but “fishnet dresses” are intended. These were normally worn over a linnen dress, but here after it had been taken off.
The bit about Egyptian advocates is not true either: there were no impediments for them practicing law, but none of them were ever given the privilege by the emperor to issue
responsa prudentium,
i.e. the responses and thoughts of jurists as a source of
ius scriptum (written law) - and that surely was not because of any wisecracks. As far as I can tell, the reason is unclear, but I suspect that it was because Egypt was the emperor's private property. Such
responsa would have binding force for any provincial judge, and no property owner would want to give such powers to any of his tenants.