I think that the generalizations about the physical appearances of unique ethnicities might be given too much importance. Those generalizations are true for a population, statistically speaking. Most would have those features. But they aren’t true for individuals. My dad is German. He looks German. But he looks nothing like the generalized German average man.
So most first century Jews would have dark hair, brown eyes, prominent noses, etc. But maybe not all! Some might have had dainty noses. Light brown hair, etc. They were supposed to be around 5’. Zaccheus wasn’t! Maybe Jesus wasn’t either!
You are right: if he was extraordinarily tall you would think they would mention it. But they might not. They didn’t ever really describe his physical characteristics at all. If they said he was short, or average, we might have more trouble there. But they didn’t. (As far as I know…)
Also, the average height for a Greek man in the first century was 5’6”. The average Roman soldier was 5’7”. So he may have stood out as a Jew, but he was surrounded by Jews, Greeks, and Romans. Maybe 6’1” wasn’t too extraordinary.