It's a great question. Like many things, you know it when you see it.
Let's contrast the Rhinoceros Party in its heyday with what's going on here. The Rhinoceros Party would run candidates across the whole country and do the work of getting a single candidate on the ballot. They would then put out a platform, which was rather satirical and funny, such as putting up a wall to keep killer bees from coming from the United States or removing the Rocky Mountains so you could coast from coast to coast on a bicycle. All of these ideas are funny. I don't think they ever impaired the ability of other voters to cast ballots and find their candidates.
This is something different. This is not even about the idea of elections. This is a committee that believes we should have a different electoral system, despite constant demonstrations that Canadians don't want that and constitutional affirmations that our electoral system is democratic. Because they're not getting it, they've decided to gum up our electoral system at the level of the ballot.
Part of the distinction is that it's having a material cost on how ballots are designed and experienced. Also, it's not actually about the election, is it? It's not about making fun of the process of whatever election we're in or some particular issue. It's about gumming up the process. That strikes me as being different from putting a satirical candidate out to get a laugh.