Without fanboy warring, memes or anything, let's discuss what will happen to this new "DCU" if Superman does the kind of numbers that the last few Marvel/DC movies do. It's releasing at the same time as a Marvel "tentpole" and also Jurassic World: Dominion which will win the most BO, out of the three. They picked the worst possible release window to put a movie this half-baked in, despite spending over 300m dollars to make it.
I think if it fails, they'll push out Lanterns (the HBO show they've already shot) but cut out the DCU connections or setup but will tax write-off Supergirl because if Superman bombs then releasing that movie is out of the question. What then? Does Zazlav sell DC? Never happening but he'll fire Gunn/Safran and dissolve DC Studios as insiders have suggested. He'll put DC back into the general IP pool WB has and go back to making standalone movies without universal bullshit which has never worked out for them. I think the only DC movie that'll get made in the near future is Constantine II and maybe Clayface. DC gets back to what it does best, standalone Elseworlds movies and they drop the "DCU".