They never considered breaking the law in any way since the ogl was not actually a license and was never enforceable. Even if they had enacted the new version there's no reason to believe it would have been legally binding since the original ogl was more of a gentleman's agreement to not bother suing everybody like tsr threatened back in the day. I spent a couple minutes looking it up and
Part 3: The Damage Done by the Otherwise Ineffectual Open Gaming License #DnD #copyright #iplaw #ogl has a detailed explanation better than I can give of the legalese side of things. Short version is that nobody has ever established whether or not you can legally protect game rules and the ogl did not do that.
I agree that it was an incredibly stupid move but the end result was that they actually listened to feedback and changed to creative commons which is something many companies would not have done. They've also opened up dndbeyond to third party materials which is something I never thought we'd ever see.