[MrFoof]

Most electronic handbrakes just push out a cam against the rotor. Most designs have a way to back the cam out with a wrench or tool.

However sometimes access can be ridiculous I believe BMW's release requires you digging around in the rear seating area for a socket to put a allen-key like shaft into to ultimately back it out. Some vehicles you'd have to jack up a corner to ultimately back it out.

It can vary widely from manufacturer to manufacturer, so it's unlikely something a recovery service would know off-hand since in general a "stuck" parking brake (or automatic transmission parking pawl) is an edge case situation for them.

[kube-system]

If the power failed on most vehicles with electronic parking brakes while you were driving, you wouldn’t have the parking brake applied. And it would remain that way. As there wouldn’t be any power to rotate the mechanism into the applied position.

[MrFoof]

No, but a situation that happened right outside my home is someone too busy looking at their phone bashed their BMW 3-series into the curb and utility pole, and then decided to put the automatic transmission in park before they got out of the vehicle.

And when they got back in, they were unable to remove it from park and put it in neutral.

The previous model you would’ve apparently been able to remove some center console trim on the transmission tunnel and insert the key into a covered keyhole to release the parking pawl. On this newer generation? Jack the car up, get underneath, remove an access panel, and then use a wrench to back out the parking pawl. What a pain in the ass.

Normal turbocharged 4-popper, not a hybrid or a BEV. Once it was put in park after a crash, car decided it was game over.

It was ultimately dragged up onto a flatbed, probably partially flatspotting the tires in the process. The guy sent by AAA had no intention (or the equipment) to safely jack up the car on a busy street to remove the pawl, and probably didn’t even want to even if he knew what to do.