Pakistan will not move past $400 billion in best case scenario. You don't simply grow just because your population grows. You grow with rise in productivity.
Many Pakis think that India's economy is bigger than them simply because our population is bigger than pakiland but reality is that even if Indian population was half of Pakistan our economy would've still been bigger than them (since our per capita income is more than twice of them despite Paki rebasing).
Given their current de-industrialisation and economic collapse, they won't be able to recover and achieve what they already used to have let alone achieve anything new.
Their lost factories are not going to return and so will all the businesses that have left them. Their macro economic crisis will never end.
Their exports haven't grown in more than a decade how do these pakis think within a decade they're gonna double their exports?
Their imports will also not grow because they'll never have the dollars to import.
If anything World Bank predicts a total rise of just 18% in per capita income of Pakistan in next 25 years or by 2047, the 100th anniversary of partition. Even that is optimistic.
If anything their per capita income will continue to shrink.
By 2035 India will be a $14 trillion to $15 trillion economy, Pakis won't even be at $400 bn.
Our exports will be around $2.5 to $3 trillion, good luck crossing even 1 or 2% of that.
If anything their rising population will make Pakistan another Afghanistan.