As you have seen, opinions vary on this topic. Your best bet is to ask your service center, or contact the manufacturer of your engine and ask them. I did, and this is what I came up with. Two stroke and four stroke carbureted outboards, running ethanol laced fuel, I always run dry after every use. I never run fuel injected outboards dry, it will damage them quickly. I try to only run non-ethanol laced fuels in them instead.
Some good fuel additives can mitigate some of the damaging effects of ethanol laced fuel and prolong storage life, but not by much. Some outboards have fuel passages containing dissimilar metals. The alcohol in todays gasoline can create an environment ripe for galvanic reaction between those metals, causing damage during extended storage and clogged fuel passages.
In addition, many older outboards contain non-metallic components which may shrink, swell, or just deteriorate when in prolonged contact with ethanol laced fuels. Running the fuel out of the engine may delay but not eliminate some of of these problems.