Say Max Baer turned pro January 1, 1970. He's the exact same fighter as he was in the reality of the 1930s. How does Max Baer do in the 70s?
He might be worse because there were significantly more partying options and a whole bunch fewer “governors” on behavior.
If Baer was trained by someone like Futch or Dundee, with more polished skills and if he got in shape then he would be a problem even for Foreman. In shape Baer with polished skills would be a danger even in 70s.
Baer doesn’t impress me much on film. One of the more overrated old timers in my opinion. Yes he beat Schmeling, but in any time period guys pull upsets. I don’t think he would become champion in the 70s because boxers with good chins always bothered Baer. So I think guys like Ali, Young, Quarry, Holmes, best him on points easy with maybe a late stoppage by Ali and Holmes. Baer also loses his size advantage that he had in the 30s with most of the fighters in the 70s. However he had big enough power and a good enough chin to beat several of the sluggers. I even think he could stun Foreman. I mean I could see him giving Foreman a brawl similar to the Lyle fight. He would certainly be dangerous to Norton. And I think he would shatter Shavers. So in short I think he’s in the mix but never champ.
His skills weren't really his problem--he hated fighting. According to his son he frequently woke up screaming at night. The whole clown persona, I think, was just to mask the deep pain he felt at having killed a man, and continuing to hit other people for a living. If you want to know how good he really was, look at the Schmeling and Galento fights, when he got an opponent he genuinely hated. The devil got loose. The answer to this question, I think, depends entirely on whether or not the real fighter, the guy he was when young, got out of him.
He was great for the 30's and 40's. I don't see him doing to well in the 70's. He'd be in and out of the top ten. He'd beat Bugner, Corletti, Richard Dunn....
He had a sturdy chin and a lot of power. And he was about 6’2” 215 lbs so he’d be reasonably sized for the 1970s. So I think he’d definitely be a contender. I just don’t see him beating the best of that period