The T-72 was supposed to have upgraded electronics in the 90s itself. Something like the MKI, the T-72 would have had progressive upgrades while they were being manufactured. This included Israeli TIs, Polish FCS along with the ability to fire Refleks.
It wasn't that our negotiation skills were bad, it is just that there was no money to pay for these upgrades. Don't forget that we were comparatively as poor as Pakistan is today when the T-72 was being manufactured in India, in the 90s. That's why the T-72s stayed as they were with only armour upgrades as manufacturing progressed.
Now 250 T-72s have already undergone the most comprehensive upgrade of the Rhino program called Gold upgrade. Another 1700 are set to follow the upgrade and is happening as we speak. The older tanks will only be lightly upgraded because of their already long life. This was supposed to have happened in the early 90s though. But started only in the early 2000s.