The majority (of the people) is afraid. Wrong sentence. Not the majority are afraid.
'Majority' can take a singular or plural verb depending on circumstances.
If you are referring to a group/number/collection of individuals, not acting together, (as in this example) it takes the plural:
"The majority of the people are afraid"
If you are referring to a collective noun acting as a single entity it takes the singular:
"The majority decides the winner."
Hm....which leads me to wonder - is the French sentence grammatically correct? Or should it be "ont peur"?
I was only speaking of English usage. For the French, we need a competent commentator.
I think you may have fallen into one of those mistakes. Collective nouns sometimes take the plural, sometimes the singular. See my comment to your previous post.
Why not "the majorité de gens"? I thought idioms relating to quantity uses de even though a word after that is plural.