This would have been a good Mythbusters. I don’t believe for a second that normal use in a modern vehicle could cause the speedometer to get stuck on the stop. In fact, what modern vehicle pegs at 90? It was common in the 80s to pin at 86, these days cars go well into the 100s
It wasn’t PEGGED at 90mph, it was PINNED at 90mph. The word PINNED means INDICATED SPEED. It was likely taken from the car computer which showed the LAST INDICATED SPEED.