Stephen Fry tweeted this video.
At least the UK is advanced enough to float a vote on this kind of system. We in the US need it desperately before two-party Sharks-and-Jets politics completely demolishes whatever governance we still have.
At this point, if a constituency distrusts the “opposition” enough, you can run a flat-earth troglodyte or a shameless graft artist (I’ve seen a face-off between these two categories more than once) and win an election. No one wants to “throw away their vote” on a third party candidate with a sensible outlook (the one I worked for howled at the moon, but that was another story).