Good points above regarding the Regional Change format beginning in 2023 and the way in which the current system works.
As far as the broader issue regarding the strength of the Eastern teams, it is and has been UConn, period. Those other teams mentioned in some cases have moved to tougher conferences but I question the premise - they were never really a huge factor on the national level to begin with.
Rutgers admittedly had some fairly decent years and lost in the Finals in 2007. Rutgers and Penn State made the Final Four in 2000 but not to the title game. And Syracuse somehow made it to the title game in 2016 despite a low seeding. I seem to recall that they lost to a pretty decent team.
Other than Connecticut, that is it for Northeast schools in the Final Four. Not much to talk about.
The Power Five conferences are also stepping it up even more when it comes to WCBB, especially the PAC 12 and the SEC.