Comparative advantage. Even if AGI is better at absolutely all work the amount of work it is capable of doing is finite. So AGI will end up mostly being used for the highest value, most differentiated work it’s capable of, and it will “trade” with humans for work where humans have a lower opportunity cost, even if it would technically be better at those tasks too.
Basically the same dynamic that you see in e.g. customer support. A company’s founder is going to be better than your typical tier 1 support person at every tier 1 support task, but the founder’s time is limited and the opportunity cost of spending their time on first-contact support is high.
I think you assume that there will only be one model. However, as we can see today, there can also be a variety of prices/qualities. Why wouldn't the tier 1 support people be also replaced, but by cheaper models?
Basically the same dynamic that you see in e.g. customer support. A company’s founder is going to be better than your typical tier 1 support person at every tier 1 support task, but the founder’s time is limited and the opportunity cost of spending their time on first-contact support is high.