Yes, Nova & UConn have won six of the past thirteen tournaments but today's Villanova appears no closer to a deep tournament run than the 2014 UConn football team was to a Fiesta bowl invitation.
I personally believe (for a number of reasons) that most BE schools will always be able to get quality coaches. Keeping them however is a different issue and aside from the two schools that have recently won national titles, Creighton may be the only one that can say that a quality, successful coach over the past decade or more hasn't moved on to greener pastures.
Xavier has been a stepping stone from at least the Pete Gillen says. Marquette lost Crean and Buzz. Butler lost Brad Stevens and Providence lost Pitino, Barnes, Gillen and Cooley (their only coaches that didn't move on were coaches they fired).
I'm not sure there is enough gravitas among the bulk of the schools in the conference to hold on to quality coaches.