Not quite right. First, Victrolas had a pitch control, so setting a different speed would be easy. Edisons were recorded at 80 rpm.
Far more significant, and what made Edisons incompatible with Victrolas, was the grooves were vertical (hill and dale) instead of lateral, like just about everybody else except Pathe. Edisons had a finer groove pitch, therefore selections could be longer than on lateral cut disks.
Because of incompatability with lateral players (think blu-ray vs hd-dvd), the business waned. Also, at least for a while, Edison insisted on being the A&R man and he had atrocious musical tastes.
The irony is that the Edison player was technically superior and arguably the sound quality of Edisons was better. I transcribe Edisons with a stereo cart, then invert one signal in software to be able to hear the music.