The legal questions that are being asked should have been settled before the referendum, particularly with regard to the constitutional and legal issues around article 50
Before the referendum everyone on both sides was perfectly clear exactly what Brexit meant. Trigger A50, negotiate trade deal and 2 years later we are sovereign again. Their were no legal questions to answer, they are only being invented because some people don't like the outcome of the vote and lawyers are lining their pockets.
That's the problem with lawyers, they are able to invent legal ambiguities to allow anyone to try and stop us leaving the EU. So even if it had said in the referendum that it was compulsory rather than advisory, lawyers could still have claimed it was illegal for any number of reasons.
The idea that voters didn't know what thy voted for and we need to know what we are getting before we leave, is a nonsense because there is no way to answer that until after we complete the negotiations.