The thing that is harder to replace is the versatility of the human form. Manual labor can't fully be replaced because robotics have yet to catch up.
>there's no need to reject the inherent value of humanity
There's no fundamental rejection here. Capitalism simply selects the most efficient methodology. If humans arent the most efficient methodology for a given task then capitalism eliminated that methodology. That's the logical extrapolation. You subjective opinions on humanities worth is irrelevant to the most likely outcome.