Sampling bias? I know plenty of leftist publications like The Wire, Scroll, News Laundry and even NDTV who are free to express their opinions without censorhip. It's just that the majority of Indians don't ,trust any documentarists anymore (leftist or rightist) because they all push their own agenda.
That claim that news outlets in general are free to express their opinions without censorship is unfortunately, not really true in practise - most outlets may express opinions but might face sanctions, bans or other forms of censorship, depending on the topic of the opinions.
NDTV has faced multiple such actions in the past (one example: https://www.dw.com/en/ridiculous-and-arbitrary-indian-journa...)
Another topic with heavy censorship is the ground situation in Kashmir. Social media and internet bans have been common since a long time (https://en.wikipedia.org/wiki/Censorship_in_Kashmir).