They/Konami/Whoever errata-ed Dark Magician of Chaos, four times in fact.
Dumb question: Why not to Pot of Greed or any of the Match Winners?
T/K/W expect that the card may be unbanned with the introduction of new cards like Thousand-Eyes Restrict where, afaik, it became unlimited without errata (Edit: Oh ok so it was actually errata-ed 5 times. Wait, so what's the difference between original and current?) after previously being banned (for way too long considering Honor Ark).
OCG vs TCG: But come on, Pot of Greed will inherently never be unbanned by the ontology/philosophy/nature/idk of trading card games.
Pot of Greed I guess could come back if the 40 card minimum is increased. Idk.
Pot of Greed could be kept banned an un-errata-ed for the traditional players.
Money that comes from making new cards instead of letting players use their old Pot of Greed cards to represent the errata-ed Pot of Greed
There may not necessarily be a way to change the Pot of Greed effect that is not to a radical* extent.
*I use 'radical' s.t. Dark Magician of Chaos did not undergo a 'radical' change. For a better word/phrasing, please suggest.