Well I can disagree with everyone of your statements, just based on my own personal experience. In the several tanks I have set up with dry rock, i had zero issues with keeping phospates in range without using any phosphate reduction media. There are many different strains of bottled bacteria that work. Ogranisms can be added either intentionally (pods for example) or by luck from frags/snails, etc. My current tank is all dry rock, over 1.5 years old, and has 0 nusiance algae, yet the rock is covered with feather dusters, sponges, and coralline. Yes, I agree, live rock is "easier" only because you just throw it in (kind of like comparing T5s to LEDs.....T5s are easier, but both work). Live rock does have the potential of introducing pests....which is why I said you need to know how to use it (and what to expect down the road). If you have set up both types, and had issues with only your dry rock setups, then I am guessing you were missing one or several of the things you listed.....the key is to make sure that doesn't happen. So to respond to your statement, it has everything to do with knowing how to treat a dry rock tank vs a live rock tank. If you just throw in dry rock, you will end up with issues. It isn't harder, there are just more steps to ensure a healthy ecosystem.It has nothing to do with "Knowing what to do" - it has to do with dry rock having no surface competition, not being phosphate stable, and not having heterotrophic organisms to immediately start outcompeting nitrogen bacteria. Coralline is a stabilizing presence. So are sponges, tunicates, worms, and the copious amounts of other organisms on live rock that are constantly eating and pooping and fighting on the surface of the rock.
You don't have to "know how to use" healthy live rock. You put it in the tank and grow corals.