I've never had any reliability problems with oil burners or oil service.
The nozzles also cost about $6 and take 2 minutes to change. Very DIY friendly as are the filter at the tank and the filter screen on the pump. I can do this level of annual service on an oil burner in 15 minutes for >$20 and also inspect the condition of the burner, soot buildup and roughly check the combustion.
Unless a problem is noted with soot buildup or poor combustion I don't need to call in anyone for service. When I see a problem I can get a service call for a hundred dollars or so since I don't have a soot vac or combustion tester and can't really justify spending the money on since a service call every few years is pretty cheap.
I did take (and pass with the highest score in the class) an oil burner service class at a local tech school so I have a pretty good idea of what I'm looking at when I inspect the burner.
Gas furnaces are not immune to problems and indeed some dangerous problems like cracked heat exchangers can go unnoticed readily on a gas furnace and actually kill you from CO buildup where the same problem on an oil furnace would typically choke you out of the house with detectable fumes before the CO would get you.
Annual inspections are an important safety requirement, whether you do them yourself with appropriate training or call someone in. Whether oil or gas the furnace does not necessarily need any actual service each year, but since you have a tech there inspecting the filters and nozzle get changed because they are too inexpensive not to just change regularly. Unless you get really dirty oil the nozzle and filters can easily last several years without problems.
I was in the northeast. I never had gas service, but I recall hearing numerous reports on the news over the years of various areas having gas service interruptions for various causes. In a large city vs. smaller suburban areas it's probably a less frequent occurrence, but when it does occur it probably affects more customers.
Why don't they have generators? Certainly loosing power can be more than an inconvenience since you can have significant losses from frozen pipes in cold weather and lost food in hot weather. A small generator is cheap insurance against those losses.
Because they are not "far more remote" unless you are in a large city.
The much higher safety risk of gas is also another reason for oil. I recall a brief ad campaign by a gas company touting gas as "Clean, Safe, Dependable" which mysteriously changed to "Clean, Dependable" presumably after a false advertising lawsuit.
Thousands of gas explosions every year vs. about zero oil explosions every year certainly calls that "Safe" claim into question. The hundreds of CO deaths each year are heavy on the gas furnace failure end due to the lower detectability of the fumes from a gas furnace vs. oil.
The cleanliness claim is also questionable since a modern properly maintained oil burner is just as clean as a modern properly maintained gas burner. The clean claim is largely based on the bogus comparison between a new gas burner and a 50yr old oil burner.
The efficiency claims you also see are also questionable with the difference between top oil and gas units being only a couple percent. Unless you have already done every possible thing you can with regards to insulating, caulking, high R windows and ERVs, that couple percent is pretty irrelevant and might save you enough to buy a cup of coffee each year.
And again being locked into a monopoly that charges you every month whether you use any product or not is the final nail in the gas coffin for me.