I think IIM Calcutta is not as recognized or talked about as IIMA or IIMB because it did not gain fame from Bollywood. Bollywood movies have been shot at IIMA and IIMB. So they are more talked about than IIMC. It has nothing to do with its own facilities. That being said, some amazing features of IIM Calcutta are

1. Top notch alumni base 

2. Beautiful campus: The campus of IIM Bangalore is not an average one. Its beautiful infrastructure and location give it a surreal ambiance.

3. Amazing Placements: IIM Calcutta is the best for finance placements. Reputed banks like Merrill, Credit Suisse, JP Morgan and Chase, Goldman Sachs prefer students of IIM Calcutta over IIMA and IIMB. For consulting IIM Calcutta has all the top 4 Mckinsey, Bain, BCG and AT Kearney.

So nothing about IIM Calcutta is less than other IIMs. It just lacks the general fame, not the works.