It's hard to gain too much insight from Wikipedia, but it looks like it fills a niche that was empty.

The Pirate Party of Canada used to be quite active on r/CanadaPolitics. Once they fleshed out their platform they ended up overlapping heavily with the NDP and Greens (particularly the Greens).

I think many Pirate Parties have fallen into similar traps when they fleshed out their platform.