I think a 49-51% inseam ratio actually looks fine if not pretty good, but you HAVE to be at least fairly tall for it to work. If you looked like him at 5’8 it would be pretty weird IMO. At 6’ it’s fine and at 6’3+ I think it actually looks great or normal.
My theory (not backed by hard data but more by visual observation) is that inseam ratio is not a simple distribution, but a three dimensional distribution. To explain, there probably is a “normal” inseam ratio mean that is 46% or so. But the taller the group of people, the higher this mean is; likewise with shorter people. E.g., 6’2” people having an average inseam ratio of 49% with a SD of 3%, and 5’4” people having an average inseam ratio of 44% with a SD of 3%, and the average (lets say 5’10) height having an inseam ratio mean of 46% with a SD of 2%.
Again, not backed by data, more of a hunch. That’s why people with stubby legs will look “short” and people with long legs will look “tall” regardless of true height. My theory is that we read people this way because we subconsciously know that tall people are “supposed” to have longer legs, and short people are “supposed” to have short ones, because we’ve seen tens or hundreds of thousands of people at various heights and our mind has equated those features with height.
Or not, I could be way off base. Just a personal theory.
Edit: a bit nonsequitor, but I’ve also noticed that in visual media, “long legs” seem to be a visual shorthand for implied height. For example, this picture of all the James Bond actors with exaggerated leg lengths to make them look super tall: