social class vs people

social class and people both are nouns.

Word	Noun	Adjective	Verb	Adverb
social class	Yes	No	No	No
people	Yes	No	Yes	No

As nouns, people is a hypernym of social class; that is, people is a word with a broader meaning than social class:

social class: people having the same social, economic, or educational status
people: (plural) any group of human beings (men or women or children) collectively

social class (noun)	people (noun)
people having the same social, economic, or educational status	(plural) any group of human beings (men or women or children) collectively
	the body of citizens of a state or country
	members of a family line
	the common people generally

social class (verb)	people (verb)
	fill with people
	furnish with people