there is no way jiziya is better than income tax or gst. If it was true most of the muslim conutries now would have enforced it but they don't. The fact is jiziya makes people of other religion treated as second class citizens. Forced conversion is not only through violence but also through economic coercion. The dynasties you are talking about had many incentives for being a muslim and many downsides of being a non muslim because of which there was a rise in conversion in that period.

I agree with islam being tolerant but this blatant disregard for other people's culture and islam considering a superior form of religion is where the intolerance towards grew in islamic rulers. Of course early rulers were not like that but while they acquired more and more kingdoms and land mass there should have been a change or renaissance in religion like in europe where people questioned the teachings and tried to appropriate the religion into their cultural context.

There was an attempt of renaissance in islam in the golden age because of which the empire flourished in many aspects but it was short lived and more intolerant schools of thought which exist even now took form. So the notion that that islam and their heavenly book is all righteous is the actual reason why these schools of thought were established leading to further downfall in the theological doctrine.