Some said that about Aczel. IMO he was never those things. In fact, he was often funny. Generally, I think people who found Peter arrogant were those who followed Harry, his associated carnival barkers, along with the rest of the TAS three-ring circus. Some claimed his prose style was exceptional, but I never found his writing impressive. Perhaps he was better than his contributors. Certainly he was not as literate, clever, or as informed as Aczel.
Personally, I can ignore a lot of arrogant pomposity as long as the person dishing it out is telling me a) something factual, b) something I didn't know before, c) something that is helpful, and d) something that allows me to dispel my own ignorance.
For his part, Gordon held the middle ground. I never thought he was anything but a gentleman, certainly opinionated, but that's why you subscribed.