I think mandatory voting probably addresses the symptom rather than the cause. If there's a lack of interest in politics, which manifests itself in people refusing to vote, forcing them to vote doesn't necessarily make them interested in politics. The phenomenon in Australia known as the “donkey” vote, in which people just fill in the ballot alphabetically because they don't know enough or they don't care enough to fill it in any other way, is very much a product of mandatory voting.
On July 26th, 2016. See this statement in context.