Green’s Dictionary of Slang

use of generic name to describe a white woman who is seen as using her inborn privilege as a means of advancement.

2017		theroot.com 29 Aug. 🌐 Becky: (noun); a white woman who uses her privilege as a weapon, a ladder or an excuse. Ex: “A random Becky hit me up on Twitter to explain why not all white women are racist.”.
2019		Twitter 1 June 🌐 I hate Beckys like this.
2021		Betoota-isms 63: Becky [...] 1. A privileged white feminist unaware of their own position of privilege 2. An upper middle class, pick-and-choose progressive who cluelessly participates in casual racism and classism.