well you are looking at your own usage of the internet. not everyone needs unlimited internet. there are a few folks who have a limited need and they would prefer it at higher speeds.
let's say i am a dad whose son is in the united states. and we do video calling on weekends for an hour or so... i had rather have a 2/4mbps line with 2GB at 500 bucks than pay higher price for the same speed through the month.
that's why i have been in favor of prepaid plans based on low cost per GB of consumption. let me use it as much as i want to. do not make speed an aspect in the pricing of the package.
Everyone does not need unlimited internet because they don't know they will need it sooner. Pay per MB is prehistoric
business model. Pay per speed is the future.
Video calling is very much possible with 512 kbps plan. I have done video chat with mom & dad, who were in Mumbai on MTNL 512 kbps. Skype works so well. That's why I said, MTNL should aim to double the speeds when feasible. So in longer term, one will not have to worry about the speed.
If the price of 2 mbps limited plan is equal to 512 kbps unlimited plan and video calling works on both, why have headaches to check usage every now and then?
Or if MTNL has customers like you, they can keep a 5th plan with 0 rental and strictly pay per used MB. But this again will complicate things.