The tories have always resisted prportional representation. They like total power, and the current system favours them in a huge way, so of course they are going to lambast PR.
They trot out the usual guff about people being confused about it, which, if you are a thick as pigshit die hard tory supporter you will agree with, but that doesn't deflect from the fact that many countries have PR with as many thick as pigshit voters we have, but they understand it!
I first read about PR in the late 70's as a student, and I've been an advocate ever since. Yes, it would lead to, for me, awful individuals with dreadful opinions being voted in to seats of power, but it would also act as a brake on extreme policies being enacted as no overall majority would be possible, and coalitions would have to be agreed between political parties to govern the country.
It would be much more representative of how a nation votes than our current system whereby one party can have, say, 35% of the vote and end up with an overall majority, but more importantly, it would encourage more people to cast their vote because it would mean something. Their vote would count.
I'm not in favour of compulsory voting. Many people at the moment feel forgotten about without a voice in parliament looking after their interests. They can't be bothered going to the polling station because nothing will change in their favour. PR would help to address that issue.
Yes, we had a referendum to introduce PR, but those that needed it the most were so disenfranchised they couldn't be bothered turning up to vote for it.