Rollover crashes are generally pretty safe assuming the roof doesn't collapse and squish you to death, and you are wearing your seatbelt. The energy dissipates without you suddenly coming to a stop like if you hit a tree. Most of the damage will be from broken windows/debris causing cuts/scratches.

If you are not wearing a seatbelt, you run the risk of being ejected from the vehicle, and the higher risk of being 'partially ejected' from the vehicle, which is often worse.

I personally observed only 1 vehicle where the roof caved in on rollover (I believe it was a mid 2000s mustang). If the driver had been a few inches taller, I imagine he would've been hurt pretty badly.

The only other time I saw a roof collapse in wasn't from a roll over, but striking a tree roof first at a high rate of speed.

The only rollover crash I ever observed that the driver couldn't walk away from was a rather fortunate partial ejection. The vehicle only rolled onto its side, pinning the drivers arm between the road and the door as it slid for a few dozen yards.

The durability of the laminated safety glass should not be understated. A fire department's extraction team's approach is likely to be "cut through the glass with a circular saw".

Granted, all of this is anecdotal, with a very small sample size. Either way, wear your seat belt.