i struggled with a cheap gasoline one for like 15 years
Emphasis mine. "Cheap" is your problem. A generator with a decent engine from a reputable manufacturer (Honda, B&S, Kohler, etc.) will start instantly every time and last for many, many years with just minimal maintenance. The 7KW unit I mentioned above cost me $699 from the local Home Depot (big box) store. It's been 100% reliable for the 6-7 years I've owned it. I use non-ethanol gasoline with Seafoam additive, and I run it for ~30 minutes each month to keep the fuel system clean and the seals from drying out.
As for gasoline engines in general, I just sold our previous snowblower. It had the original 10HP Briggs & Stratton gasoline engine that it came with when I bought it 20+ years ago, and it ran perfectly. The only reason I sold it was to buy a larger, wider snowblower because we now live where we get even more snow and have an even longer driveway.
Also the factor of draining fuel (usually wait for it to cool some what) is annoying as hell.
If you run it ~30 minutes once a month, you don't have to drain anything. I've never drained the 7KW generator, not even once. As for seasonal engines (like snowblowers), those get drained at the end of each season if convenient, otherwise they get topped off with treated non-ethanol fuel to minimize the air volume that can cause condensation during storage.
BTW you can get a kit to refurbish generators to run on propane, i.e. the tiny honda generators.
That flexibility is indeed cool, but propane has less energy content per unit volume and unit weight than does gasoline so you take a performance hit. Plus, the container for five gallons (or any other volume) of propane is a larger and heavier than for gasoline. If you're going to run the generator for just a few hours, you can fill its integrated tank and then you don't need to lug an entirely separate fuel tank, hose assembly, and regulator - just pick up the generator (like it was designed) and go.
Hmm... I wonder if folks who have done that propane conversion have TWO propane tanks. If not, then they are offline while they take the tank somewhere to get it refilled with propane. With gasoline, a single five gallon can will keep the generator's integrated tank filled, and the generator running, indefinitely. Fill up the integrated tank and the generator keeps running for hours and hours while you take your time going to a nearby gas station.
Add to that the fact that gasoline is available almost anywhere, 24/7 with a credit card, and is self-serve (none of which are true at least here in the States). Finally, if you don't use the gasoline in your generator (or lawn mower or weed eater or jetski or ATV or boat or...) you can always just pour it into your car.
It's very difficult to beat the flexibility, convenience, ease of access, breadth of use, and availability of gasoline. I do fire my grill with
itpropane, but only because my present house doesn't have a NatGas fitting on the deck. My last house did, and I rejetted the grill to burn NatGas so I didn't have to lug around those propane bottles nor have the risk of running out of propane. Your comment did just give me a flashback, though... back when we used to go tent camping, all of our Coleman equipment (stove, lantern, etc.) were dual fuel specifically so we could use gasoline. As you said, one single fuel to power everything, including the vehicle that drove us back home.
EDIT: Corrected mistype of "it" to "propane".