Due to scheduling conflicts and possibly three not good movies behind him, Henry Cavill is out as Superman in the DCEU. Warner Bros. was trying to get Cavill to make a cameo in Shazam!, but negotiations broke down.
Warner's issued a statement regarding Cavill, which didn't clarifying much.
"While no decisions have been made regarding any upcoming Superman films, we've always had great respect for and a great relationship with Henry Cavill, and that remains unchanged."
The studio is shifting focus towards a Supergirl origin movie, which would mean that Kal-El would be an infant, effectively ageing out Cavill in the role. A solo Superman movie isn't likely to made anytime soon and Cavill has other potential franchises on his hands.