It won't be right to say that they revolutionised Bollywood cinema but it slightly disrupted the traditional norms of mainstream Indian cinema. They pushed the structural boundaries and filmmakers started embracing unfiltered storytelling.
Before Delhi Belly, adult comedies in Bollywood were largely restricted to slapstick and double meaning comedies. Here, the film was with unfiltered cuss words with almost 70% in (English/Hinglish) reflecting how urban Indian millennials actually spoke.
This change in the “Bollywood language template” was also seen in films like Gangs of Wasseypur and Badlapur. Also, the conversational realism over written melodrama could be noted.
The Dirty Picture proved that a woman could carry a mainstream box-office film to massive commercial success without a male superstar. It gave rise to women-centric films with bold treatment like Heroine, Hate Story series, Jism 2 etc.
But this revolution was somewhat shortlived due to pushbacks from Censor Board and political groups later in the decade with films like Go, Goa, Gone, Hunterrr, Lipstick Under My Burkha etc.
Finally, the true spiritual successor to this revolution was the birth of Indian OTT streaming platforms (like Netflix & Amazon Prime Video). The above mentioned films in the question laid the groundwork for unfiltered storytelling seen in shows like Sacred Games, Mirzapur and modern dark comedies.
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