Now if you didn't need cash for spending if you had a pension or SS that covered all expenses, then I could see the argument for auto reinvestment.
It doesn't make sense in that situation either, as explained:
Automatic reinvest creates additional shares at the dividend distribution price. It's nice to get more shares, but: (1) may not fit in with your asset allocation plan, and, (2) creates a bookkeeping nightmare.
If taxable divs aren't needed for spending, allocate them according to your AA.