라고 불리다

is called; is known as

The passive of 부르다 'to call', used to give what something is named without saying who does the naming. Every line here is that: 새우깡은 국민 과자라고 불릴 정도로 'Saeukkang is practically called the national snack', 중소기업이라고 불리는 곳 'places that get called small and medium enterprises.' Speakers use it when explaining a term to an audience, which makes it sound a step more formal than 라고 하다 or the active 라고 부르다.

Register: explanatory, slightly formal