Let's look at the history of New 52. Dan Didio tried to push New 52 line of comics through for a long time. Finally getting a high position in DC he put the New 52 gears in motion. There came Flashpoint which eneded with Pandora re-writing the reality and Barry Allen jump starting Pandora's work. That was a way for DC to put Wildstorm, Vertigo and DC multiverse together.
Now you could also draw a vague conclusion that Belloc was the person who created New 52 when he put 3 different Multiverses together. But she probably meant Luciferverse, Silver City and DC. Against popular belief I have to inform that Silver City and DC Heavenare not the same thing. Silver City exists outside The Multiverse as an elite pocket dimension where only the chosen can enter.
Now after few years of New 52 comic books DC needed to change offices moving to WB who owns DC. To combat office moving they created Convergence which again set the Multiverse gears in motion. This time Braniac wiped the New 52 away and brought back the infinite Multiverse. That happened because Dsn Didio didn't want DC to have a canon. Instead there is an infnite Multiverse with with each Universe having it's own canon. Basically everything is Canon now, yes even Elseworld is now canon specifically stated by Dan himself in an interview.
The ideas and concepts that took place in Elseworlds are part of the continuity now
So that is the history and explanation of New 52 references in movies, TV shows and comic book. The real question here is should we stop with all the New 52 references since New 52, well, it literally doesn't exist anymore. Not only is there now an infinite Multiverse, the New 52 brand was discontinued. Hence you don't see it on comic book issues after Convergence.
The current main continuity is called Post-Flashpoint in the sense as last one was called Pre-crisis. At one point the references are getting old and people even though claim to hate it don't wanna drop the brand.
There was a great character that was ruined for the New 52 joke. She is called Fifty Sue.
I wrote this post to give an in depth explanation about New 52 references to people who can't only read DC all the time. The post was influenced by Flash Season 2 Episode 2 52 breaches.