On a more serious note, I think this is one of those questions where the answer is, "it depends". If you are coastal cruising in generally populated areas, aka pretty much all of the US coast line, I would carry minimal spares...............
I agree. I haven't yet cruised anywhere TowBoatUS wouldn't come and get me and tow me to where I could get parts.
That said, I do carry a few spares and of course filters. The only spare I can recall using while away from home is the pair of belts for the alternator and water pump. The old belts didn't break but they looked pretty ragged and I decided that replacing them before it was an emergency would be a good idea.
I had to replace a transmission oil cooler once while cruising and it was a weekend so I had to stay in a marina longer than I had planned, but I had a replacement air shipped and installed it and was on my way.