The EST of NXT
I believe that Charlotte won not only to inflate her title reigns so she can eventually pass her father, but to protect Rhea from being booed against a hot, freshly returned Io Shirai. They probably have seen the seeds of backlash on social media and don't want a Roman Reigns situation to occur with their new top prospect. If Rhea wrestled Io by the time the fans return to arenas, the people's choice would be very obvious at the next TakeOver. Having a villain like Charlotte be the champion against Io would guarantee the desired reaction for both parties.