Upon having just worked on a saw with bunged up threads on the end of the crank it would seem that it's an issue with some, as well as stripped threads are still threads for retaining nuts.

In the Husqvarna 2100 repair manual the tool listed to take the entire crankcase apart is, a brass hammer. This being 1970's tech, that's long been over with, and better things have come along since.
I have flywheel knocker tools from Stihl, Husqvarna and Echo, as well as flywheel pullers, except for Echo, they just have the one knocker tool with different thread adapters.
Pullers are great to use, sometimes even they need a whack with a hammer on the stubbornest of flywheels to release.
Knocker tools can be made simply and easily if so desired, either with a nut, a hunk of pipe and a welder, or a piece of round stock and drill and tap.
Yes, crankshafts can be bent, just like anything else, but removing the flywheel isn't an issue and has to be done to service the saw.