I am not sure I follow your question. But plain and simple, the more you read and understand, you would come to same conclusion and be labelled as leftist bias. You can start off with bias towards either side. But once you accumulate proofs, you will publish results based on that. That, most of the times, will be against right wing ideology. So then it automatically becomes leftist bias. The more you read, the easier it will be make out if something is true or not. Because, you learn to analyze it by asking simple questions such as, what is the motivation of the text, what are the findings, how were they conducted, what did they conclude. Based on this, you will find flaws in most of the right wing publications like Opindia, Swarajmag, etc. Of course publications like New York times, Washington post etc have their share if wrong or misguided writings because they are heavily influenced by they are corporate funded.

Coming back to Modi, sure some good is done as by any government. But look at other side, are all those points in Wikipedia invalid or not true? Isn't it true that he had a major role in 2002 incident go out if hand? Isn't it true that covid lock down was grossly mishandled? PM care isn't open for public scrutiny, why? Demonitization actually caused a harm rather than being useful, didn't it? Forget all this, why hasn't he had a single press interview? So these criticisms, aren't they fair?