It's a matter of the available talent pool.
There are more tall men then short men.

Tall men are ordinary and no body notices them unless they are extraordinarily tall like a basketball player.

So when the tall man dresses, he becomes a very noticiable tall girl on the far right end of the bell curve. GGs are rarely as tall as the average male.

Short men only become average sized GGs, which makes shopping for clothes very easy.

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At 163cm/5'-4", I make for an average sized GG.
At 170cm/5'-7", there are few GG taller, but many more men who are taller.
At 168cm/5'-10", the number of men taller than this begin to diminish.
Why Sex Differences Don’t Always Measure Up