While Boston and Philadelphia both have their similarities in both cities being in the East Coast and both being important in the country’s founding, I believe the MBTA has two advantages over Philadelphia:coverage and continuous expansion and restoration of it’s mass transit system.
One can go from North Station to Lowell, Lawrence, Newburyport, and if the yokels of NH were smart enough, they’d welcome MBTA to NH while in South Station, one can go to Worcester, Plymouth, Brockton, and as far as Providence and TF Green. Philadelphia used to provide rail service to Allentown, Reading, West Chester, and the Jersey Shore but no more.
However, a commuter rail extension in RI to Wickford Junction is in the works last time I checked and another extension to Fall River and New Bedford is already going to come to fruition (
https://www.wpri.com/news/local-news...-rail-service/;
https://www.boston.com/news/local-ne...ll-river-mbta/).
I haven’t really seen nor heard of anything important that SEPTA is doing and the closest is the proposal to extend the Purple Line to KOP and I’m not sure if that’s going to happen, even with President Biden sitting in office. It’s really no surprise that the MBTA, like many transit agencies across the country has it’s problems with age, but is also able to expand and restore many of its lines as well as create new lines like the Green Line extension to Tufts while SEPTA continues to sit on it’s hands and provides subpar service for both urban and suburban residents.