10 Ways The DC Extended Universe Could End
5. DC Rebirth Hard Reboots The Series
DC's Rebirth event wasn't a reboot per se, but an attempt to improve the New 52 era by adding cherrypicked elements from pre-Flashpoint continuity. The history and legacy that had been discarded was partially restored.
As far as the DC Extended Universe is concerned, a loose Rebirth adaptation could go one better than that and serve as a hard reboot of the series, a movie that dismantles the franchise to pave the way for it to be literally reborn.
The comic book event thrust mainline DC continuity and the Watchmen universe into the mix together and revealed that Doctor Manhattan was the one behind the New 52 status quo shift, rather it being The Flash's time-meddling.
Legal red tape could make it difficult, since the character is due to appear in a big-budget TV series over at HBO, but bringing Doctor Manhattan into the DCEU would give Warner Bros the opportunity to do pretty much anything. This is a character who could unmake the universe by snapping his fingers, or turn it into something different.
The studio could essentially weave a hard reboot into the story, and from there, the possibilities are endless. They could follow the comics and adapt the Watchmen-Justice League crossover, Doomsday Clock, or start afresh with a clean slate.