He is a Mary Sue/John Doe style character that really only has just a few glaring weaknesses as well. He is predictable and lackluster. I don't like him. It's simply my own personal opinion. Everyone is entitled to one.
Even so, I have read one or two comics with Superman that I did enjoy.
I hear people say this a lot, but I don't agree. Yes, he's powerful, but in the frame of his own stories he has things that give him a challenge and can supersede his abilities. Sure if he swoops in to fight normal thugs in Gotham he'll have no problem, but when he's facing Luthor, Parasite, Mongul, or the other cosmic or magical horrors he often faces, he's in trouble. I like that not all of his struggles are physical, but mental. The thing is, a lot of the modern day stories are obsessed with making Superman frequently prone to going on the dark side and I find that absolutely tired and predictable. I love Batman as well (when I was a kid, the mountain of Batman figures and hours spent watching BTAS and the movies are a testament to that), but I feel he falls more into the Marty Stu territory that people would like to admit.
In my opinion, when written lazily and poorly, Batman becomes Batgod. Yes there's the perception of him being mortal and vulnerable because he's human, but seriously, at times he can be written as a man 12 steps ahead of God with planning and infallible backups, capable of deducing any weakness and being able to defeat anyone or anything no matter how dynamic in scope because preptime.
Now, I know Batman isn't always like that and neither is Superman, but if you view their attibutes in a certain way, they come off as terrible or amazing.
Good
Superman:
Upstanding, Champion of the weak and becon of inspiration and hope
Indomitable will
Patient, socialble, friend to citizens of the world
Has Godline powers, yet shows humility, grace, love and patience to humanity
Batman:
Unbreakable resolve
Powerful mind and skills, yet never forgets to aid the weak and often brings in victims of tragedy into the fold
Capable of doing good outside of beating up criminals and aids through charity, resolving incidents through smarts, willing to forgive and has in the past given villains second chances etc
Has a fatherly passion for his city and people
Bad:
Superman:
Numerous super powers capable of devastating armies, two major weakness (kryptonite and magic), can punch planents into orbit,
practically immortal
One True Hope for humanity, yet easily goes evil and loopy and drunk with power
Can easily win a battle
Batman:
No powers, around his 30s yet knows every major martial art and translated them into a hybrid style, world's greatest detective, chemist, psychologist, escpape artist, mechanic, pilot, inventor
Has billions of dollars to buy and get anything he needs, Silverspoon in his mouth, not in danger of "real world dangers" like rent, poverty
In all the countless elsworlds and out of continuity stories where various heroes go through corruption, he is a paragon of gritty strength that neeeeeeever goes the evil path and is tasked with showing them the truth path of justice.
Both characters have great backgrounds, yet both have potential to be eye rolling if seen through a filter. There's tradeoffs depending on the writer and medium.
Both have different advantages and disadvantes in both aspects of their life:
Superman has all this power, yet, he embraces the Clark Kent identity and puts his whole into journalism to help people in a different way than crime fighting when able. Despite powers, had to work hard to get where he is (through schooling, patience and restraint, struggles with identity due to not being human)
Bruce is supremely intelligent, has billions at his disposal and an inventor, yet, instead of being outclassed by his superhuman peers, always keeps fighting to improve himself through mind and body.
Batman is noble and dark, yet can be cold and standoffish to even his own family.
Superman is the guy who has a huge heart; he frequently signs autographs for kids, interacts socially with citizens when the danger has passed and is a public figure and role model, yet, this can strain him and put him into a limited role. He has to constantly be aware of what he's doing or else the public can easily turn against him due to holding him to an unrealistic ideal. He is powerful, but he's not a God. He has to deal with the reality that he cannot save everyone. He someitmes can be manipulated and led into disaster because of his big heart and compassion and altruism.
Sorry for the wall of text, I get why you don't like the character, I just wanted to present a different perspective of what he can be and why I like him.