Not what you think wrote:
Do old runners exaggerate their best times from when they were younger because they simply do not remember them? Or they lie once about them, and nobody is informed enough to call them out, so it becomes easier and easier to say faster and faster times until it becomes such an unrealistic situation. The lie is now true for them, because they start to believe their own B.S.
Back in HS, I identified as a football player and wannabe sprinter. Running distance was the 1 mile run I did maybe 3-4 times a year. So anything distance related, I didn't really understand it all.
There was a picture of my ex gf's Dad running a race sometime in the 80's in their home, he looked pretty ripped, and he joked one time, "yeah before that race I smoked a few cigs, funny to think back to those days," he was a pretty avid runner too throughout the years.
Out of nowhere, maybe too much caffeine, had me look up his name and I saw a few results and the one was a 1:20 HM in the early 80s. Pretty damn impressive for a guy that just worked at a local plant, and smoked half a pack a day. He has to be in his early 70s now I am guessing.