Sufficiently advanced AI could create bots to do the things they need done. We cannot create an ant equivalent bot (yet). Messengers on horses don't exist alongside the car, plane, or internet. Bots created by AI will likely fit the needs they have much more neatly and for lower maintenance costs than paying humans.
We are everyday finding new ways to automate human labor, from mental to physical to creative. Why would AI suddenly stop that effort in order to trade with us?
if you don't believe this will happen not much matters in financial markets. i am unsure what your investment strategy should look like if you don't believe this. or said another way, it's a bit of a pascals investment. either you believe this and win or you don't believe this and lose out regardless of positive or negative outcome.