Because there is no need
It is very clear , who are we talking about
No point in taking their Dirty Name
Secondly even after Uri , he never said Pakistan
And his first statement came after 6 days in Kerala
Ok let me explain
why it is important to clearly spell out names .
First, It clearly asserts to international community that nations as whole has decided to stand behind the political establishment in retaliation against "other nation-state" ( and not some rag-tag 'terrorist' organisation).
Second, it removes confusion among our own citizens that we are fighting against a "regular nation-state"(in this case pakistan") , and not some other actors . As historically war was always fought between nation-states so , clearly spelling out name of enemy state helps to create that psychological picture in citizens mind.
Third, it calls bullshit about imported terms like "hybrid warfare", "state and non-state actors" . AS by clearly pointing out the enemy nation-state , we declare to international community that we don't differentiate between terrorist or regular soldier , as they trained and provided from same place only , so any violence inflicted on our nation by any such actor is an act of aggression by enemy state and not by some disgruntled terrorist organisation.
Fourth, in continuation of above , by calling bullshit about "hybrid warfare" , we assert our overwhelming conventional military power and put pakistani military on back-foot. So, it's advantageous for us to clearly call such act of violence as act of aggression by enemy state , thus automatically opening option for retaliation as is done in case of cross border shelling and thus pakistani military directly pays the price and not these canon-fodder terrorist.