This has nothing to do with admin support, it has everything to do with the reality in which these kids live.
In my twenty plus years in the classroom, SES is a greater indicator of success than any other measurable metric. If it weren't, we'd see much different representation at SMC finals.
Want to know why some of those "great programs" from the 1990s and 2000s aren't quite as great anymore? Look how their demographics shifted due to new schools opening, to population shifts, and to the changes in white collar and blue collar employment in an area. Yes, in many cases, directors have moved on as well - but how many of those directors might've stayed if their programs weren't completely changing out from under them? Or if the kids in their programs weren't going from upper middle class to lower working class in the span of five years?
Admin support is what takes good programs to great - but going from "ok" to "good" requires a teacher who is willing to confront the challenges in a program head on. If you don't recognize that there are unique challenges to working in rural, semi-rural, and urban areas, you're completely out of touch with reality.