To all those that say diesel is safer than gas...
I would agree that poured into a bilge, gas is more flammable than diesel.
Gas engines on boats that are fuel injected, have no open gas. I have a gasoline boat today and the only time I smell gasoline is when I'm filling up the gas tank or changing the fuel filter.
Older gasoline inboards which have a carburetor require a blower and adequate ventilation and a spark arrester to prevent such explosions. This seems inherently 'bad' in my opinion. My last boat had a 5.0l V8 260HP gasoline inboard (stern drive). It was fuel injected. Again, I never smelled gasoline unless I was filling the fuel tank. Fuel injected gasoline boats don't have open fumes as the gasoline is contained within the enclosed fuel system.
As far as diesel, it's not hard to find a recent fire on a boat with a diesel engine. Maybe it was electrical? Boat fires happen to diesel boats as well as gas boats.
Personally, I wouldn't want an inboard again (gas or diesel) mainly because I'm tired of working in cramp spaces. My last boat had an inboard engine (stern drive). It was $1,500 in labor to pull the entire engine out. The fuel pump was on the bottom of the engine and only accessible with the engine out of the boat. This was part of the reason why I went with an outboard. The other reason was speed.
I can cruise comfortably at 25 kts, with almost the same efficiency as a diesel boat. Sure diesel is less expensive than gas. So I pay a premium to get somewhere in 1/2 the time. Or to cover twice the distance in the same amount of engine hours.
I would also note, I see lots of folks with diesel boats who have portable gasoline generators and gasoline outboards for their dingy's. I have to assume there's a portable gasoline container onboard somewhere.
Walking through the Seattle boat show in Jan 2020, it was quite apparent that outboards, which already were popular, are even more so today. Bowriders, which used to be equipped with inboard gas engines and stern drives are now offered with an outboard instead. They're efficient, easy to work on, easier to replace.
If I were to look at a diesel inboard, I'd want something with 2,000 gallons of diesel onboard so I could get to Hawaii. For inter-coastal cruising, I prefer the outboard with a 150nm range between gas stations.
That said, I would love to see an RT-29 with twin outboards. But with RT having the RT-27 OB and the RT-29 as diesel/inboard, is a fantastic lineup. If I were them I'd leave it the same. But if they ever did come out with a RT-29 with twin outboards, I'd be interested. I just won't hold my breath and will enjoy my RT-27 OB today.