Has an Olympic Basketball (Men) game ever ended 90-80?
Exactly once. On August 8, 1992, Brazil beat Australia 90-80, and no Olympic Basketball (Men) game before or since has ended that way. When it happened it was a scorigami, the first 90-80 in league history.
That makes 90-80 the 126th most common final score out of 698 that have ever occurred in Olympic Basketball (Men). One point away, 91-80 has happened 1 times and 90-81 has happened 1 times.