Comment by t-writescode

Neither. They're describing the philosophical similarities of:

  * "Has only been that way so far because that's how computers are" and
  * "I just want to center the damn content.
     I don't much care about the intricacies of using
     auto-margin, flexbox, css grid, align-content, etc."

Centering a div is seen as difficult because complexities that boil down to "that's just how computers are", and they find (imo rightful) frustration in that.