Safe Harbour, it is relatively easy to get cash out of tax-deferred when one has significant assets in non-tax-deferred that are not cash.
One does this by a double-exchange as described in this link: Placing Cash Needs in a Tax-Advantaged Account - Bogleheads
It does not matter if stocks have gone down, sideways, or up. One does not end up "selling low" when converting their stocks in their taxable accounts into cash. The reason is that they buy the same stocks in their tax-advantaged accounts with the cash found there.
Unfortunately, some folks do not understand what a double exchange is, so then end up paying more taxes needlessly.