I’m no expert, but 40 hours of maintenance probably isn’t one tech working 9-5 for a week.
Depot service hours only matter in a budgetary sense, although I heard they were immense for the F-14. All those moving wing parts need to be removed, inspected, x-rayed or magnafluxed or whatever they did, reassembled, and exhaustively tested. In comparison, on the flight line day to day, I don't recall hearing the jet required unusually more time than similar aircraft.
The time the F-14s spend sitting inside hangars (and requirements of trained techs to work on them) being useless was the primary driver of their retirement. Carrier hangar space and tech numbers are very limited after all.
Using made up numbers, its fine if each F-14 requires twice the maint of a F-18 if a mission pack for a F-14 takes two birds but doing the same mission with F-18 would require at least four.
On the other hand depot level longer term service certainly was a budget buster for the F-14 and if you can pay for depot level service for 100 F18 for the price of 10 F14, well, the fleet's getting F18s.