This isn't true. Their more recent Primo line may only offer a 35mm but that's not the widest offered by Panavision now or historically. In fact, their wider offerings are in their smaller, lighter line for use in applications like hand-held, steadicam, etc. Sounds like DSLR territory to me.
Diopter diameter may not be the most appropriate way of determining widest taking lens but neither is personal bias.