The rule in effect is rather narrow and doesn't actually ban home manufacturing. All the elements of a kit are still accessible and legal.
The only difference is that all the parts to finish the controlled part can't be sold together. So like you could by the 80% from one shop online and the jig from a different shop online. All the other parts wouldn't be affected in general, maybe an issue if sold with the 80%. And there are also other ways to do home manufacturing that would be completely unaffected but the rule.
Also the case isn't done. The order is a temporary stay where the court is asking the ATF lawyers to explain things.