Is Sir Keir Starmer the ‘most unpopular’ PM in recent times?

The claim that Sir Keir Starmer is the 'most unpopular' PM in recent times cannot be substantiated with the provided sources. There are no direct polling data or metrics available for comparison to other prime ministers. Additionally, the timeframe 'recent times' is not clearly defined, making it difficult to make a definitive statement about his popularity relative to others. Without a comprehensive overview of political leaders' popularity over time, it is impossible to verify this claim.