Re: I did about 10 years on bikes.
40+ years here, legs (and other parts) still intact.
My dad was the same. 40 years, no major problems (barring a black cab ignoring a give way and knocking him off resulting in a fractured shoulder).
It was at about 43 years when a car came out of a side turning, straight into the side of him, crushing his ankle against the engine of the bike and breaking his leg in 2 places. After a month in hospital and a year or so with an agonising metal frame screwed around, and into, his leg and several operations to rebuild his ankle which had pretty much disintegrated, then another 6 months or so with a big boot thing, he could almost walk normally. Several years later he still can't walk for that long, or bend it properly.
The surgeon said that had it happened 20 years earlier they just would have amputated it as it was only more modern techniques and equipment that allowed them to save it.
My uncle was a police bike rider for 25 years with a faultless record, and then retired to Cornwall and bought a Harley. One day he woke up underneath a lorry with an air ambulance parked in the field next to him. He was ok, fortunately.
Don't count your chickens...