It’s not ubiquitous, you’re gonna be up there with air hoses anyways, what’s a couple of power cords. A roof is generally clear and free of obstacles so there’s not much for your cord to get hung up on. Far different than working within the structure of a house.
Cordless saws seem to fall off roofs easier and get lost easier … the cord from a saw is very handy for locating it. If you rig it correctly, you can safely raise and lower the saw by the cord, so you’re not climbing a ladder one-handed. Nothing more frustrating than your battery dying up on a roof.
The biggest advantage of cordless saws is that you’re not gonna trip the breaker on the one 15a outlet the homeowner lets you use. Not an issue for new construction, where you have a couple of 20a outlets set up with the temporary service.
It’s been a few years since I framed full time so maybe things have changed.