1. He avoided or didn’t fight most of the divisions top big men and big hitters 2. Nearly knocked out by featherfisted Brian London. Referee would have stopped the fight if he wasn’t saved by the bell 3. One Patterson left hook left him convulsing https://goo.gl/images/VWVCa9 How would Johansson’s chin have stood up to a hitter like Liston or Foreman or Frazier or Louis?
With the gloves back then every punch felt like a rock, he could take a punch , but just tended to get hit solid when tagged , he didn't really 'ride a punch' , probably his lack of head movement.
I am not that familiar with the quality of the British/European heavies, from 1956 to 1960, but analyzing Ingo's fight record during that period, you can see via good management (take that as you may), Ingo was like the "perfect storm" and got the first title shot with some good fortune. Yes, he crushed #1 ranked Machen in Rd 1, but Ingo mentioned he was considering fighting Angelo Dundee's Willie Pastrano at the same time period (Summer/Fall 1958). Ingo's later encounter with Cassius Clay in sparring, did not go well for Ingo......and might have been the same result against Pastrano, who was a "dancing master" too. Plus, the Cus D'amato factor, who was looking for a "marketable", but not grossly threatening challenger (i.e. Liston) to fight. But you can't fault Ingo, when he got his Title shot #1, he crushed Patterson.
In the title of your thread you did ask if he could take a punch... And then in the post you did ask if he could take the power of several of the hardest punchers in history.... There is a huge jump between these 2 thing don't you think?