OK, What's Wrong With Propane Generators?

Cost to operate. They do run cleaner and require less attention.

ours is a propane ,hardly used. its all in the way you camp. some campers are always plugged into shore power others sometimes . propane burns cleaner engine stats cleaner.

a diesel genset will run from the main fuel tank and have a lot more fuel available
also diesel has more BTUs per gallon than propane, so the same KW genset will use less diesel per hour for the same load, than one running on propane

when OUR safaris were built diesel generator were NOT a common option, being larger and more expensive than the LP onan

They are reliable , run clean.
Problem is if you boondock or tailgate a lot you have to refill your lp tank every 30 hours or so.

The biggest drawback is fuel. You use a lot of it. If you are out in the summer, and need to run the generator 12 hours or more a day, it will use a LOT of fuel. And, it is harder to transport propane to your campsite.

If you have a diesel generator, you can run a long time on the fuel in your tank.

My Bluebird has a 300 gallon diesel tank. I can run the generator a loooong time! Even with a 80 to 100 gallon tank, it will last many days. And, you can transport more in fuel cans, and dump in the tank if needed. Harder to refuel propane.

If you only do a couple days at a time, then the propane is a pretty good deal.