Pre-Wonder Woman, maybe this sort of Days of Future Past-style continuity shift would have made a little sense, but still, a reboot at this stage in the game feels fairly extreme.
As was mentioned above, Flashpoint was essentially a means to reboot the DC Universe as a fresh jumping on point for readers.
Plus, with Wonder Woman 2 slated for right after, it seems unlikely that some big reboot is in the works.
By building towards it, it’s understandable to think that the DCEU is in for some kind of reboot, though I’m inclined to think this would be a small scale one.