The series finale of Batman: The Brave and The Bold centered around a selfish individual with the power to make a perfect world but doesn't and instead utterly wrecks an existing one because he thinks causing it to reboot will get the universe he thinks he wants and deserves, inadvertently causing his own demise. It ends on a bittersweet note that Batman and the rest of the characters have accepted their own deaths and choose to spend their last moments together. Batman ends it on the hope that a Batman will always exist to fight crime and save lives.The last scene in Batman: The Brave And The Bold was Batman looking into the camera and telling the kids at home upset about the series ending that Batman will always be out there fighting crime for them. How you can compare something so bittersweet and perfect to the horrific thing I just saw is beyond me.
The series finale of these movies played out because of an individual who came from a well meaning place to keep his world safe but instead inadvertently causes its own destruction. It ends on a bittersweet note with the remains of the Justice League and Teen Titans facing certain death as Earth's last days are marked. Constantine decides to end it by convincing Flash to reboot the universe on the hope they can get it right next time instead of just accepting this Earth's destruction and being wiped from existence.
Yes, there are a lot of glaring differences like the horrific violence and deaths but a lot of parallels.