They do have nearly identical *steering" geometry. It also makes sense that frames for taller riders would have a longer front center for the weight distribution, although on small sizes they sort of forget about that and favor avoiding toe overlap instead. And a taller rider is also more likely to want more stack, although that can be obtained with tall risers on the bars and sometimes is.
The rest is marketing, pure and simple.
Now tell me what functional difference it could possibly make if you need to move your pads behind the basebar to get the reach you want, or flip the stem to get the rise you want.
Why would I as a taller rider want more stack? The bike I have ridden for years has small stack and I love it for some reasons I already posted. But am I missing something?
Taller riders generally need a fit with more stack. Your bike doesn’t have a low stack, just low relative to other frames of similar size. You don’t fit a bike by a ratio of stack to reach, you match the stack to your fit and the reach to your fit.
Why do tall rider need a bike with more stack? Just is not making sense. More reach I understand, but why more stack? I am tall and sure am not seeing I need it. I can make up for anything I need
with a long seat post and stacking on the front if needed.
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