That would be pretty uncommon and if the damage was that severe I’m sure he had a lot of headaches to deal with the insurance claim.
The majority of rentals are people flying into an airport and grabbing a car to get to the hotel and a meeting. The last thing they want to do is damage the car.

I’ve noticed on forums you’ll see two types of posts. It’s people that have never owned a former rental and tell you about how badly they’re abused or people who have and would do it again.

I’ve owned two. The first I had three years of trouble free driving and sold it for a few thousand less than I paid.

Most recently I bought a 2019 Ford Fusion Hybrid with 16,000 miles. Still under factory warranty. I paid less than half the MSRP. With a Ford there are a couple of Ford dealers who sell factory warranties online at a significant discount. Since mine was under warranty I was able to extend the factory warranty to 100,000 miles or 6 years for $1,000. Check Flood Ford or Ziegler Ford. This would have been $2,600 through Ford online or my local dealer. It’s the same Ford warranty and shows on my Ford online account. Totally legitimate.

I’d be reluctant to buy a high mileage rental. Under warranty with the ability to extend is important IMO. The lower the mileage the less likely it ran into an abusive rental customer.

At one point in a previous decade I worked for a rent a car company. Not hertz but another large one. Trust me when I tell you those cars get used hard. Even at low mileage.

A Canadian man is being charged $18K for damage to a rental car. He said he never took it out of the city, rental company says it appears to have been taken off road. Driver claims it's a defective transmission. Be interesting to see who has the burden of proof:

https://youtu.be/Zhn7F2TcmVI

They are "saying" that the damage occurred during his rental, but they would need to prove this and need solid information for this that is not disputable. At the very least, I would request this information formally from the rental company before anything. If they have the proof, they should be happy to provide it. The guy in the video basically covers the questions I would have. Having rented many vehicles, the rental agency primary concern is to turn the vehicle around and get it making money again. I've gotten plenty of screwed up vehicles with obvious things that were not caught because no real inspection was done from the previous rental.