Winning seats proportional to a party's vote share grants them legitimacy and support exactly in proportion to the support they already have and that got them e

Winning seats proportional to a party's vote share grants them legitimacy and support exactly in proportion to the support they already have and that got them elected. For actual decision-making power, they need a parliamentary majority, which by design requires the support of a majority of voters. I hope the UK system isn't quite so rigged as to deny any seats even to a party that gets >50% of votes.