"By great dancer I mean the moves that a normal bollywood heroine can not perform without her getting into the dance steps."
Bollywood dance became a form much recently. And our movies choreography was an extension of classical dance & has been that way for long.
You forgetting the main part of many of the dancers you praise today have learnt dancing from Madhuri Dixit or watching her only. Current choreography may heavily be inspired from the street forms but bare no 2 cents infront of mainstream dance formats & nowhere stand a chance opposite classical art.
Shakti is a trained dancer. So is Madhuri. Shakti isn't better because she does acrobatic moves or imbibes several formats into one act.
Dancing is not about certain steps. It's an art form to express. There is literally no value for anybody doing steps. Ofcourse not everybody can produce navarasas in their act but not every act required them to either. And there was no need of any dancing in Dekha Hai Pehli Baar but still there was a choreography filled with adayein. The right amount.
Like I said, it's pointless when you compare with some xyz dancer. Go back 10-12 years, there was no lockin' n poppin' being that famous in India. DID brought it but didn't invent it. And whatever you see now on reality shows, the ones who are actually trained classically rank above others. Because every little move comes out as art. Right from their eye movent to even the way they pose. And the true talent comes out when this is in perfect control & the post is perfectly landed to the beat. Untrained dancers don't get it.
So when we say Natya Shastra, it is strictly not limited to Indian art of dancing. Likewise, when you say "dance", the laya, bhava, mudras etc take over & you'll know Natya Shastra is in every dance format that exists, that is being created right now.
Why Madhuri Dixit dance skills are perfect is solely because she has perfected the art of communicating via dance. The surreal experience where her body is not the only thing dancing. You wanna compare, then Katrina Kaif lags here no matter how much praise she gets as a dancer, best of current time but never overall. Madhuri is no match to Vyjayanthimala or Hema Malini. The Choreography in the 70s & 80s were much different doesn't mean they're weak..dance forms evolved from back then. Not the other way around.