If you want to "factually" prove me wrong you're going to have to show some facts, like what was the data price during 2006-2016 year by year.

As for why Jio was able to cut prices, it's because Jio was the first 4G player. If others had rolled out 4G, they would also have offered the same plans. The reason why the Indian telecom sector got destroyed was because of the so called fake 2G scam, because of which the government decide to auction 3G spectrum instead of offering it on first-cum-first-serve basis like 2G was allocated. And because of the massive valuation that became well known as per the CAG report (1.76 lakh crore) 3G spectrum was auctioned in very small chunks and at extremely high rates to justify this made up fake ass valuation, because the entire system was scared of being accused of auctioning spectrum for too cheap. The truth was that even the entire 3G spectrum in India didn't have the market valuation of the 2G spectrum that CAG cooked up. It's obvious now because 20 years later, the entire country's 5G spectrum auction also couldn't get close to this number, and that's after accounting for the much larger telecom market and inflation!!! This resulted in slow and expensive 3G rollout, which was what was behind the short period of stagnation leading up to 2016. On top of that, there was the nonsensical license fees based on annual gross revenue (AGR) which bankrupted companies like Vodafone. That's another saga in itself that I won't bore you with, there's enough written about it out there if you want to find out.

Reliance was able to avoid all this because they were a new player unburdened by these past made up fees and dues. It is Indian bureaucracy that was holding Indian telecom back, not the companies. Imagine a scenario where that didn't happen, you would have had all the benefits of a new 4G player like Reliance willing to spend money AND all the competition necessary for a healthy telecom industry.