Properly understood, the political economy looks like this: developers + renters + construction workers on Team Build More Housing, and incumbent landowners on Team NIMBY.
You often see renters working against their own interests by opposing new development, mistakenly believing that stopping new housing from getting built will somehow reverse the upward climb of land prices. They should really be rooting for developers to dump more apartment units on the neighborhood, and quickly, to keep the supply of apartments nice and slack.
Neighborhoods with good connections to center city Philly are only going to see their land prices keep climbing. Whether or not rents stay affordable will be determined by how many apartment units those land costs can be spread across. The more housing units that get built on the expensive land, the lower the rents.