Mark Waid's issue with The Man of Steel was simply that John Byrne replaced the Silver Age/Bronze Age Mort Weisinger Superman that Mark Waid loved with an updated version of Superman that was closer to the Golden Age Superman, instead of the Silver Age/Bronze Age Superman from Mark Waid's childhood. Mark Waid admitted, "I was one of the wailers years ago when Byrne did his stint." http://www.comicbookresources.com/?page=article&id=2595
There is no more "real" version of Superman than the original Golden Age version that was conceived and created by Jerry Siegel and Joe Shuster. And The Man of Steel returned Superman closer to the Golden Age roots, while also updating Superman for a contemporary audience.
The Man of Steel restored Superman's uniqueness as the Sole Survivor of Krypton. In the Golden Age this was the standard.
With Silver Age Mort Weisinger concepts of Krypto the Super Dog, Beppo the Super Monkey, Kara Zor-El Supergirl, the Argo City citizens in the Survival Zone, and millions of Kryptonians in the Bottled City of Kandor, etc., in the Silver Age/Bronze Age one began to wonder if anybody really died when Krypton exploded.
The Man of Steel returned to Clark's powers gradually developing, multiplying as he grew over the years, as Jerry Siegel had intended.
The Silver Age/Bronze Age Mort Weisinger Superman feels like a "stranger in a strange land", and pines for Krypton, says "Great Rao" and spends his spare time in a Fortress shrine to Krypton in solitude. The Golden Age Superman by Jerry Siegel didn't pine for Krypton, he was upbeat, smiling, secure hero, with a sly sense of humor, and toyed with criminals humorously.
John Byrne brought that back in The Man of Steel.
John Byrne had Clark Kent display some confidence, exhibiting some aggressiveness and bravery again, which Siegel had Clark display in the Golden Age.
John Byrne scaled back Superman's powers closer to the original Golden Age power level, giving Superman limitations again. He couldn't time travel, he couldn't move planets around, or survive without any air indefinitely, he had to noticeably strain and struggle against super-powered foes. The Man of Steel brought back Lois as a tough, competitive, aggressive reporter, making her a much more independent and sane character again than the Silver Age/Bronze Age Weisinger Lois spending her life trying to get Superman to marry her and prove that Clark Kent and Superman are the same person. As soon as DC gave Siegel and Shuster the boot the Lois who was supposed to be Clark’s independent, feisty, strong-willed rival reporter competing for stories was turned into a woman intent on proving that Clark Kent is Superman.
Superman was originally a champion of the oppressed versus corruption of the law at the highest levels, rich corrupt LexCorp Lex Luthor hiding behind a mask of respectability was a return to that concept. The Man of Steel brought Luthor closer to his roots. Luthor was originally a red haired dictator - a ruler who assumes sole and absolute power. He wore business suits. Here is Luthor in Superman #4 (1940), written by Jerry Siegel and drawn by Paul Cassidy.
Luthor in The Man of Steel was red haired and wore business suits and was certainly a ruler assuming sole and absolute power. He was also a con-man. He had scientists working for him and Jerry Siegel's Golden Age Luthor had a scientific lab assistant working for him. Luthor originally met Superman as an adult and hated Superman because he's powers were a threat. The Man of Steel was a return to that concept.
Why is bring a character back to it's roots good? To get back closer to what it was meant to be. It does make sense from a entertainment and business stand point to get back closer to what made Superman such a hit in the first place. The Man of Steel realized that and presented Superman, Lois, Luthor closer to Jerry Siegel's creation.
"I have taken my standard 'Back to the Basics' approach," John Byrne says about his work on Superman. "Everything that has accumulated over the years has been the result of people trying to do something different. So now I'm taking Superman back to the basics, and that becomes different because it hasn't been done in so long. It's basically Siegel and Shuster's Superman meets the Fleischer Superman in 1986."
The Man of Steel has an obvious connection and continuity throughout. It's the modern age updating of Superman's origin and big events in his history, like his first meeting Lois, Luthor, Batman, etc., for a contemporary audience.
Birthright is a lot of Silver Age nostalgia and pandering to the Smallville TV show fans. There is no need for Birthright, Superman: Secret Origin and the current rebooted Action Comics to exist. Like Batman: Year One (1986), if it isn't broken, don't fix it, and The Man of Steel (1986) wasn't broken.
I always highly recommend The Man of Steel...