No, you are wrong. DBZ in the late 80's and 90's was huge in Europe, megahuge, more than Pokémon. It just happens the US got DB very late. By the age they were whatching DBZ we already finished GT, and DBZ ended for us more than half a decade ago.

That's not exactly true, The Cell and Buu sagas were aired on US TV after only a small delay from the Japanese release and local television was airing the Frieza saga on from the mid 90s.

We got the Frieza saga in early 90's. Very early.

I think it's not such a useful debate. All of the early anime that was popular early on outside of Japan was undoubtedly influential and important part of the popularity of anime outside of the US, but Dragonball Z really had a special spot in that it had pretty large mainstream appeal and aired during normal afternoon blocks on American TV -- while Sailor Moon was known when I was growing up, I remember it being on early morning (06:00) cartoon blocks, so it was kind of out of the way. That isn't to diminish the influence of Sailor Moon, Saint Seiya, etc, but at least in the United States DBZ was a cartoon you talked about at school because "everyone" watched it and was waiting for the rest to be translated and dubbed.

I think that's mostly what the GP meant, and I would agree it was quite significant in this regard.

Funny, it was the other way for me. Dragonball was on in the early mornings and Sailor Moon was in the afternoon.

I don't recall Sailor Moon ever approaching the popularity of DBZ (in the United States at least). It seemed like every kid in America was glued to the TV in the 90s watching DBZ on Toonami. Pokemon was probably more popular than DBZ, but much of that was due to the influence of the Pokemon Game Boy games, and obviously the trading card game.

I think DBZ was the first massively popular anime in the western world that leaned heavily into the shonen tropes. Pokemon appealed more to a younger audience, and Sailor Moon was more of a shojo anime.