Yeah. To my understanding you have to show up, but do you have to vote, or vote correctly?
Here in the US supposedly the 10% of dumbest voters who deign bothering to show up supposedly decide all elections, the swing/swayable voters. A sizable % of these have no guiding political philosophy they can express. So it’s not like we are guided by the majority’s deep understanding, it’s supposedly the voters that were swayed somehow.
Freegards
You are supposed to vote correctly, but as it is a secret ballot (and we take that seriously - we think we invented the concept) there's no way anybody can check that you have - so in practice, yes, people can just spoil their ballot, or submit a blank one. But that's a loophole - not a deliberately designed feature.