We are already at a point where we can trick large number of the population, it can without a doubt close the gap even further where we question anything and everything.
Beyond forensics, which require large capital investment and operating costs, to be able to detect AI vs human content will be limited in terms of access. It will be so that its not that we can't detect AI content anymore its that most people cannot afford the service to detect it and thus they lose interest.
This has side effect of making live performances by humans scarce and in valuable.