Rule lawyering doesn’t really take you that far regarding this issue because wigs are explicitly forbidden and hair extensions that try to imitate actual hair are forbidden, and the people using them are cursed. The hair extension rule, according to most interpretations applies to all kinds of materials that are attached to the hair and look like it, so maybe you can just not attach it to your hair directly, but I can’t see how that might help.
If he was planning on making another open world blocky game like Minecraft, it would have failed, no question. Minecraft is not only an open world game, but a modable one with a huge community. Everything Notch might have been thinking about adding/removing/tweaking about Minecraft would have already been done by some mod.
It would have been pointless.