There are legitimate reasons for using a modern Diesel engine as a stationary power source, but generally speaking RV use is not one of those. Diesel engines rated for on-highway use that see a lot of stationary use need to be able to do a manual regen when necessary. The manual regen is also a stationary process, and if you think an idling Diesel is annoying, you should see/hear/smell one that's doing a stationary exhaust cleaning. That process can go on for 30-40 minutes at times, and the RPM's can get quite high.
:):)