That's just your nostalgia talking. The game was really that pixelated. Source: I still play those games on an actual, old-as-fuck computer. The pixels really were that big. But I like big pixels and I cannot lie.
I thought he was more saying CRT monitors hid a lot of that, which is true to some extent. It's why there are "CRT filters" in pixel game emulators, even though they suck ass.