I hasten to add that DC was hyping up something like this for DCYou, and all the happened was Johns JL ignored the status quo of Batman and Superman. I don’t think it will be as extreme as rumors make it out to be.
Vast swaths of DC continuity are already pointless. Byrne’s stuff is out and has been for a while. They retconned WW’s origin again, meaning Rucka’s origin got retconned out. Nothing from Pre-FP Aquaman has carried over. The past 30 years continuity is already patchy at best.