Semantic Differential

Surveys or questionnaires using the semantic differential question is the most reliable way to get information on people’s emotional attitude towards a topic of interest. [1]

Measurement of subjective attitude by using polar opposites - Wikipedia - [2]

It works because of its simplicity - it is straightforward. [3]

It works better than Likert Scale because it works with polar opposites. [4]

Semantic Differential vs Likert

In short, the key difference between the two scales is that semantic differential scales measure attitudes towards an object using a set of bipolar adjectives, while the Likert scales measure the degree of agreement or disagreement with a statement or question. That is it, literally speaking.[5].

But the question arises, why is semantic differential more effective than Likert scale? I would derive that Likert provides feedback to leading questions, which by default starts on a wrong footing. You want to start with neutral opinion, expressing a wide range (polarity),

Likert asks the respondent to respond to our question, rather than express their feeling or emotion. [6]

SD is less biased and requires more cognitive effort (abstraction) than Likert. [7]. Indeed, Likert suffers from acquiescence bias and social-desirability bias.