Between balance of probabilities I woiuld say marginally in favour of "Yes". The maximum danger of Balkanization is yet to come in India whereas Pakistan has almost weathered the storm. The problem begins to take hold when the lower 25% of population claw out of abject poverty - both in economic and sociological terms. Meaning when the lower 25% have food in their stomachs and heir minds are freed from the tradition that held their generations in mental servitude.
The tradition that held them in servitide for generations could be feudalism, religious myths [this could be Christian, Muslim or Hindu etc]. As a society develops at some point the bottom 25% begin looking beyond hunger and traditional order begins to decay as increased urbanization takes place. This creates state of flux. This flux is composed of massive number of poor in urban areas who are discontented and open to any radical movement offering a new order.
Europe went through this during 17th-19th centuries leading to wars, civil wars, revolutions which broke the old empires creating plethora of new nation states. It took more wars to finally bring a a new order of peace post WW2.
Think about this. The British ruled all of present day India, Bangladesh, Burma, Pakistan with a few thousand officials? How was that possible? Don't forget the British Raj lasted over 150 years or twice longer than present day India or Pakistan. The reason was a indolent, oppressed natives. And to be sure they had been oppressed well before the first gora sahib showed up. Had they not been so you think few gora sahibs could have conquered such a entire continent? They did so because majority wa sleeping under the twin evils of poverty and local myths.
In 2020 as urbanization is taking hold in India [Pakistan is far ahead of India in urbanization] the traditional order that is kept 100s of millions of Indians sedated is breaking down. This will lead to release of huge energy. In Pakistan this was harvested by the far right religious groups [TLP, JI etc] and in India this is being harvested by far right Hindutwa.
However as we move forward there is possibility of secular groups, either clustered around language, regional or socialist movements to take root. When the horizontal division [caste etc] breaks down there is a possibility of regional nationalist movements [vertical] to take root like Tamil, Sikh etc taking root.
To offset that the India state could successfully integrate these forces into a wider co-prosperity zone of united India. This has worked nicely so far with Sikhs who have been bought out by massive advantage via higher share in military, agriculture etc. How well India can deal with the far larger populations across India is to be seen.
We must keep in mind India is purely a British construct. Large political units only existed in South Asia because of 'foreign invaders'. We have to go back to Ashoka's time to see any real desi super-state. Rest of the time South Asia resembled Europe. Loads of states.
So never say never. I saw the sudden collapse of Soviet Union. Or Yugoslavia etc. To be sure India faces lot of uncertainity over the next 50 years as the old oder gives to the new.
So, this is basically leading an argument without grounding it... a projection. Europe after centuries of strife, strongmen, royals, autocrats, dictators, fascists and two world wars, is still superficially connected, a common cause in prosperity notwithstanding.
As it stands the strongest and most organized state apparatus still exists in Europe, a crutch for all that bureaucracy to exist and state to bear down on it's subjects, democracy notwithstanding... Brexit and to a lesser extent Catalonia, Yellow Jackets, Flanders, Wallonia, Faroe Islands, Basque, Irish, Scott, Occitans so on and so forth remain causes seeking appropriate time, cognition, traction and a path...
Anywhere, people have kept their former identities, distinction or just a historic grievance/cause alive have found a way to keep it/them simmering, at times with very long odds. This, without foreign organized intervention and general prosperity on the face of it...
Yugoslavia and Soviet Union kept states for the sake of it with utter disregard of human cost... in early 20th century death tolls in millions were par for the course...
In each case a core group/ideology defined state, being ruthless and willing to kill irrespective of costs have managed states and kingdoms... India just defined that(core), and for now it is reinforcing it's ideology on confirmation bias until it reaches a rigid ultra puritan, reichstag fire, with us or against us stage... internal disintegration will only ensue after this whole charade comes full cycle. How it actually pans out is yet to be seen, disintegration remains the most likely outcome.