If towing toys you can prop almost any engine for fast take off and thrust.
Maybe those who comment should mention what they use their boats for and roughly the hours per year they normally do.
I do long trips offshore then troll for several hours clocking around 300-400hrs per year on my 4 strokes. Servicing is straight forward as basikly it's much the same as doing any car.
Modern 2 strokes were popular for a while out here but most soon went back to 4 strokes. Water police, maritime, fisheries, marine park boats, water taxis, oyster boats and just about all small commercial fishing boats are now back to the 4s.
The Australian boating community is quite large with over 250,000 registered boats alone in my state, we also have the weather for all year round boating.
With yam and merc claiming 80% of the US market that doesn't leave much for the others.
I know from being a marine rescue volunteer which engines fail more than any other out here !!(not what I have)!!