Not because they have much to do with larger leftist goals necessarily, but because the potential for redpilling people is high.

Just speaking for myself, one of the first stepping stones in my path from liberalism to socialism was learning about things like Duverger's law. I remember having a period when I was 18 or 19 and still a left-liberal in which I went through a slow discovery process that was something like this:

• I don't like the two-party system. I wish we had a viable party that was anti-war, anti-mass-surveillance, and pro-drug-legalization.
• Well, why do we have a two-party system?
• Is it simply because most people like one of the two major parties, and third parties just aren't that popular?
• No, the two parties are actually quite unpopular
• Okay, so why do people vote for only the two major parties if they don't like the two major parties?
• because we have a dumb voting system that produces spoiler effects and creates incentives for voters and political office holders to coalesce into two major parties
• Okay, how do we get rid of that voting system and establish one that can support multiple viable parties?
• Can we vote in people who have election reform in their platform?
• Probably not, because in order to get into office, they'll have to run on the ticket of one of the two parties, and neither of the two parties is going to provide electoral support to a candidate who wants to advance an electoral system that would weaken them. So it's a catch-22. You can't succeed in the two-party system by undermining it.
• Okay, so what would it take to implement an electoral system that can support multiple parties?
• Most likely case? Massive amounts of popular unrest and disobedience. Probably so massive that it would be tantamount to a revolution.

Gotta say, I definitely think it made me more open to revolution when I realized that even something fairly minor, like creating a multi-party political system, would require one.