The break-up of the Big East had a great effect on Women's Basketball. In 2012-13, the conference featured UConn and Notre Dame, the two National finalists, plus Louisville and Syracuse; a pair of top 25 programs. DePaul, Villanova and South Florida were also solid teams that year.
Of those programs, only South Florida ended up in the American with UConn and I'll maintain that being in the American was the start of the slide from perennial champions to contenders. The sport as a whole has caught up with UConn and I think the AAC dulled its edge a bit. That may well have happened in the Big East had UConn thrown in with the BB onlies because, again, the better programs left for "greener" pastures.
In seven years in the AAC, the UConn women didn't lose a conference game. 118 regular season (three 18-0 and four 16-0 seasons) and 21 conference tournament games. Since returning to the BE, they are 70-3 (18-0/16-1/18-2/18-0) and are 12-0 in BET games. FWIW, in that 2012-13 season they lost two league games (to ND).
I don't know how much it matters but I do think the Big East is a better league (even more so after the last round of realignment) and is better preparation for UConn's real season.