I believe we say "the purpose of a system is what it does" is to also poke at the fact that there are mechanisms and design decisions (tradeoffs) at play that lead to certain results, and that if we want to change outcomes, we need to change the system.

Votes matter more in some systems than others. Preference voting allows for smaller parties to more easily gain seats while first-past-the-post supports two-party systems. In the UK and AU, the prime minister must hold a seat, and so can be removed from parliament through (a subset of) citizen votes removing them from their seat, even if the majority party stays in power. In the US, the President (who can issue executive orders) is elected by an electoral college--none of whom are directly elected by citizen votes. Maybe it's not a big conspiracy, but these systems are doing what they are known to do, and will do so unless they are changed.

Of course there are systems in place to change these systems, which are also quite hard to utilise. And strangely (or not), no one is rushing to improve voter power and representation. So there's some interesting questions there around what changes can be made that would best improve representation, and what could be blocking those changes from being made.