It was relatively big on other places as well and the anime was broadcast for quite a while, it's just not as big as the likes of One Piece, Naruto or even Yugioh which aired at the same time and overshadowed it and it also ended way sooner than those, right before social media became a big thing.
Plus, considering we're like nearing two decades from the heyday of this series if you're young enough i'm not surprised you didn't hear about it before.