While Alicia De Larrocha and Vladimir Ashkenazy had hand spans smaller than those of many (mostly male) concert pianists, they were much larger than those of a big majority of adult women! https://www.aliciadelarrocha.com/en/content/her-hands
They could both just reach a 10th in their youth, which means their maximum hand span between thumb and fifth finger must have been at least 8.5 inches (21.6 cm). This is more than half an inch (1.2 cm) bigger than a woman with an ‘average’ span for their gender. Only about 12% of women can play a 10th – many struggle to reach a 9th.
Despite this, Alicia wanted Steinway to make her a keyboard with narrower keys, like they did for Josef Hofmann early last century, but this request was not granted. Ashkenazy now deals with arthritis in his hands. https://www.playbill.com/article/vladimir-ashkenazy-says-he-is-giving-up-piano?fbclid=IwAR3pQ0zQXAZ54xnBwqYybZOpwxWNqqo_AqMdD32RTN9QB-Y08CR7rzgzxis
Further information on pianists’ hand spans: http://smallpianokeyboards.org/pianists-hand-spans/
Records of prize winners in the most prestigious international piano competitions show that men significantly outnumber women. For first prize winners the gender difference is even more stark.
This gender disparity can be explained by the significant difference in hand spans between males and females, and the demands of the range of repertoire expected.
You can see the statistics here: http://smallpianokeyboards.org/competition-results
This gender disparity does not occur in Mozart and Bach competitions, where women are much more on a ‘level playing field’ with men.
How many potential world class pianists cannot reach their potential due to having to play on a keyboard that is way too big for their hands and also puts them at risk of injury? It turns out to be more than 85% of women and 25% of men who are disadvantaged by today’s conventional keyboard!