In my basement utility / laundry area I have a half dozen fluorescent fixtures. Two fixtures have newer electronic ballasts and 4 have magnetic ballasts. It seems the lamps last forever with the mag ballasts but not so long with the newer electronic ballasts. The lamps are 1970s vintage F40T12, when I bought the new fixtures I was careful to get (and had a hard time finding) fixtures that could use my old lamps.
Just from common sense it seems it would be harder on the lamps, since they turn on instantly with the newer ballasts, but are “ramped up” with the magnetic ballasts.
If you frequently turn the lights on and off, that would certainly reduce the lifetime in either case, but more in the case of an “instant on” lamp, where current starts flowing before the cathodes warm up, resulting in stripping of the emission material; this is why you hear that CFLs shouldn’t be turned on and off frequently and is a big factor behind the complaints of short-lived CFLs. It’s possible that there are more complex/expensive electronic ballast designs that preheat the cathodes, with a longer turn-on delay (or conversely, some electronic ballasts may not even bother heating the cathodes, operating the lamp as a cold-cathode lamp, which isn’t good unless it was designed for this operation).