Delta is pricing one-way Los Angeles – San Francisco awards (that would cost $72 to buy) at just 5000 miles. That’s all part and parcel of reducing the mileage cost of cheap flights, and ultimately increasing the mileage cost of expensive flights.
Put another way, the ‘standard’ 25,000 mile domestic award’s days are numbered at Delta. And along with it, the possibility of generating outsized value from Delta miles. Which also means it makes no sense to choose to earn Delta miles over another currency.