Selling a Car - Would you Buy if Dealer Service Was Stopped

Any potential buyer doesn't know if you are mechanically minded or highly skilled. Or even a bodger. But age and brand of car will make the difference. 
If we are talking Porsche or similar, you would be crazy, but it's a Ford and although it may effect resale, not like it would other brands

If you intend to sell it at some point then a service history is going to add some value, but more than what you save by doing the work yourself? If you intend to keep the car until it becomes uneconomic to maintain, then future value is irrelevant.

Also, and not to be dismissive, but it's a Ford Kuga, not likely a future classic, it will be worth half of bugger all at 10 years or 100,000 miles.

Depends how old the vehicle is. Anything more than 6 or 7 years old, wouldn't bother me much. Different vehicles will be affected more, as they'll attract a different buyer and certain demographics will appreciate the comfort blanket of a FDSH