Everyone should participate and have their voices heard. However, if you think the whole thing is a farce and want to undermine the system from the get go, I'm not gonna be too broken up about it if you choose to exclude your voice from the process.
In some countries (I think Australia is one), you're required by law to vote. If you don't, you get a small fine. I think we need this system because there are a ton of would-be voters who don't see the point. If they were made to vote, I think there'd be greater engagement because they'd be more frustrated at the appalling candidates and demand more because they had skin in the game.
Pretty positively. Our politics have trended generally to the right as have most western countries (especially those with large Murdoch media owned presences) but the 2 major parties still sit relatively close to centre, and particularly wild right wing elements have been shredded at the last round of elections.
The hard-rights attempts at US style minority led major parties seem to be invalidated by the voting population, so I'd say our system of ranked choice voting with mandatory participation is working very well.