Same thing it does now. AGI isn't enough to have a command economy.

https://en.wikipedia.org/wiki/The_Use_of_Knowledge_in_Societ...

https://en.wikipedia.org/wiki/Economic_calculation_problem

nb I am not endorsing Austrian economics but it is a pretty good overview of a problem nobody has solved yet. Modern society has only existed for 100ish years so you can never be too sure about anything.