Beyoncé gained more impact over the years by making smart career moves (ex. going solo after Destiny's Child). Rihanna gained a lot (dare I say the same amount) of success in a shorter period of time for being managed well by her label. The choices made in her career helped her propel to superstar status in no time.
Rihanna had the opportunity to break out in the digital era with annual releases. She made a huge impact, there's no denying it, but Bey has well over a decades worth of accomplishments and impact, it goes way back, she's a household name, and she goes beyond the music. Her name alone is very significant to black culture.
every female artist is inspired by Beyonce and tries to be like Beyonce
Rihanna has no impact at all no matter how many no.1 she has....she dominates the radio but she is just a hit maker nothing more sorry