This is an effort from DC to bring back old readers and hopefully gain new younger readers as well.
DC is going for the pre flashpoint era universe by bringing back specific characters while incorporating some new and younger heroes elsewhere in their line.
Also there seems to be like a few of every character. Like 3 supermen, 4 flashes, 4 jokers. Etc etc.
And this is their second reboot since their New 52 relaunch few years back. The new52 was basically kept afloat by the most overrated Batman run I've ever run. It was a hipster party for some strange reason