Median build year in Buffalo runs around 1952, noticeably older than the 1973 median across the wider service area. That twenty-year gap isn't trivia - it's the difference between a door built on hardware from the 1950s and 60s and the newer stock going up elsewhere in the 1970s through 1990s. Older Buffalo homes are more likely to have had at least one door swap already, sometimes more than one, and the tracks, jamb brackets, and header framing underneath can still be original even where the door itself isn't.
With a house this age, the first thing we check isn't the door - it's what it's hanging from. Jambs settle, headers sag a little, and a replacement door installed square to a frame that's no longer square causes problems that look like a bad opener or a bad spring but aren't. We see this more here than in newer parts of the service area simply because the houses have had seventy-plus years to move.