Just my opinion (and I'm not short), but... Being short and stocky was an actual "thing" insofar as Wolverine's personality in the '80s and '90s. He'd often "square off" with an opponent and they'd literally be looking down on him, as if to be under-estimating him. His fearlessness despite his stature is what helped to MAKE him who he was. It was constantly reinforced that, like a real Wolverine, he was small, but wasn't to be messed with. His height/build was literally part of his character. For us older guys to see him be portrayed by someone taller/thinner than the illustrations/stories we grew up on takes some of the familiarity we had for the character. My younger siblings complain about the change in aesthetics of the Teenage Mutant Ninja Turtles from one movie to another, so I think it's a fair thing to have a minor gripe about.

Awful take. Wolverine being short and hairy was a deliberate part of his physical character design for the entire history of the X-Men comic. It's a character design trait that really didn't need to be changed for the film at all. Jackman does a great job as the character so it's mostly irrelevant now but the annoyance was just because if you're going to make a comic book movie at least try to represent the characters that everyone already knows (unless it's a problematic representation).

In summary it made a lot of comic fans unhappy because it was ignoring a major element of the characters visual design. Remember this was an era where comic book movies were absolute trash because the writers/directors/producers didn't seem to give a shit about the source material, so casting a tall lean wolverine was not a great confidence booster.

It's not because short men don't feel represented.

And again, it didn't really matter in the end cos we got a great Logan out of Jackman, but it was a legit gripe.