Although when it's asked which are the best bollywood films of all time, people all name all the Blockbuster films like Sholay, Mother India, Mughal-E-Azam, Hum Aapke Hain Koun etc. So yes, some blockbusters do represent a special form of artistry. The art of connecting with classes and masses alike.
It is tough in bollywood to make a blockbuster movie.
Think of making a movie under 10 Cr. and earning 100 Cr.
Is it possible ?
Or making a movie in 300 Cr. and making 1800 Cr.
Its very very tough. So it is more of economics rather than art form. Minimization of cost and maximization of profit.