A house built around 1976 almost always started with a single steel door, no insulation layer, and extension springs mounted along the horizontal track rather than a torsion bar over the opening. A lot of those original doors are long gone, but the extension spring setup often survived one or two door replacements because nobody touched the track hardware. That's the stuff that gets dangerous when it fails - an extension spring under tension, with a frayed or missing safety cable, is a different repair than a torsion spring job.
Openers from that era, or even the first wave of replacements in the 80s and 90s, were chain-drive units with no battery backup and limited rolling-code security. We still find them running. They work until a gear set strips or a logic board dies, usually without warning.
Cold matters here too. Steel contracts in deep cold, and a door that was slightly out of adjustment in August will bind or refuse to seal in January. That's not a Mounds View quirk specifically - it's the whole severe-cold band this area sits in - but combined with original 1970s hardware, it shows up as a specific pattern: stiff rollers, a cable that's lost just enough slack, a sensor that reads fine until the temperature drops.