Absolute Superman is what the New 52 version of Superman was aiming for but failed to be
The New 52 reboot of the DC universe came with a lot of changes, primarily to the timeline. Decades of DC history got truncated to having happened within just a 5 year span, and all the characters became younger with new designs meant for the "modern era".
Aside from surface level changes, it also came with a couple of characterization changes for the DC big names. Some characters, like Batman, basically survived the reboot with minimal changes to how they were characterized and written. Other characters, namely Superman, underwent a pretty marked change in personality as DC editorial tried to use this reboot as a chance to retool the character.
The New 52 reboot happened in the early 2010s, when cynicism and edgelord content was still at the height of their powers. Superman was considered doddering and old-fashioned, boring and preachy. In the eyes of Superman detractors, he was like their boomer dad lecturing you on his Kryptonian soapbox. DC decided that Superman needed to be younger, more edgier, more sarcastic and arrogant, more modern and with the times.
Meet New 52 Superman, a version of Superman with all of the same backstory elements and relationships with his parents, but is inexplicably way more of a dick. He's brash, arrogant, isn't afraid of using his full strength, intimidates people and quips A LOT more. Previously, Superman wasn't really known for throwing verbal jabs while fighting, but New 52 Superman was a real chatterbox in that department and came replete with an arsenal of Joss Whedon-ass one liners. If you've ever seen an anime where there's one really strong guy that completely dominates fights and knows they're untouchable and is flippant about that fact, that was the vibe of New 52 Superman. He was more Gojo Satoru than paragon symbol of justice.
Alongside the personality changes, they also did away with his classic suit and gave him a more armored, sleek design where his costume gained a lot of weird techno-lines running across his body and most importantly, they ditched his speedo in favor of a belt.
Reception was mixed, but as the 2010s wore on, people really started to turn on this version of Superman. People missed the classic personality and look of Superman and wanted him back. DC started to backpedal and slowly began to change how they wrote New 52 Superman. He started acting a lot more like his pre New 52 self. They started to hone in a lot more on classic Superman elements, like giving him a relationship with Lois Lane, which had previously been replaced in the New 52 with him dating Wonder Woman. Soon, DC fully gave up and just killed New 52 Superman off entirely and replaced him with his literal pre-Reboot self from another universe, complete with his own Lois Lane who he was married to. New 52 Superman sucking so hard was unironically the catalyst for DC Rebirth, a second round of soft reboots that aimed to restore elements of the pre-reboot comics that people liked.
So after all that, people were worried when they started to reveal details about the brand new Absolute Universe's version of Superman. All of the elements that made New 52 Superman fall flat on his face were seemingly making a return. His suit looked more techno-armor than ever before, with speedo once again being replaced by a belt. His hairstyle and general vibes felt like a return to the 2010s edge, and he was described as a Superman with less love and hope than the mainline one by DC editorial. People were immediately against him on principle, and everyone braced for what seemed like New 52 Superman Take 2.
Then the Absolute Superman comics actually came out and they somehow made the character work. Just like people thought, this version of Superman is a lot more brash and confrontational than the mainline Superman. He's younger (both in age and vibes) and has a more brooding vibe than the clean cut Mr. Sunshine vibes of the original. He is a bit edgy and moody, and he has a bit more of an arrogant streak than traditional Superman. So far, this is sounding like a repeat of New 52. So what actually makes him work?
I think what makes this characterization of Superman work while the New 52 one fell flat, is that he has a different backstory and role in the wider universe. New 52 Superman nominally had the same backstory as the old one. He was still raised by the Kents, and still inhabited the same structural role of being the paragon hero who sets the standard for heroism. Superman being kind of assholey while still being in the same position felt incongruent. The Absolute Universe made sure to deviate Superman's role in this new universe far enough away so his new characterization actually makes sense in context.
They basically made Superman into a vigilante that fights against the system instead of defending the system as a champion hero. Superman isn't accepted in the Absolute Universe, he's a fugitive actively being hunted for being an "illegal alien". His main foes are corporations and mercenaries working for said corporations. His entire backstory recontextualized his parents as working class people who suffered under the oppression of a fascist ruling class, and he himself grew up in that society instead of being a newborn sent away on the eve of its destruction. It makes sense for this version of Superman to have more of an edge than the mainline universe Superman because he personally witnessed profound tragedy. Superman traditionally has a pretty cushy childhood and grew up in a positive and nurturing environment. He knows Krypton exploded, but he's too young to remember anything and his parents are just a recording, not people he knew enough to properly mourn. He had a good support network of people who accepted him and showed him unconditional love. It's hard to believe any person raised by the Kents can grow up to be anything other than a good-natured guy. But Absolute Superman, the refugee of a fascist planet who saw everyone he loved get constantly beaten down by authorities until the whole planet blew up; that guy I can believe would have some rough edges.
Basically, they made a punk version of Superman, the real definition of punk instead of the performative punk Superman they made for the New 52 to revamp his public image.