Some exceptional women will beat men, even very good ones. This isn't news.
Exceptional as she was, wasn't the male record that Beryl beat a long distance one? A 12 hour time trial in which she rode 270 miles. It's well known that ultra events whether running, walking, or cycling, often reduce the performance gap between male and female because overall conditioning and mental toughness come into play rather than just pure strength, speed, power. Her record lasted 2 years.
If she wasn't an outlier lots of other female cyclists would still be breaking male records surely.