I’ve seen a lot of terrible dry exhaust designs/executions. Don’t know why it’s done poorly so often, but I’ve never had a single problem or issue with my dry installs. Key is to insulate the exhaust pipe in the engine room, put a shroud around the pipe where it exits the deck, place the muffler in the aluminum shroud that keeps everything dry, have a removable cap that covers the shroud top, and run the exhaust to the height you prefer.
Having said that, I prefer a wet system unless the application requires dry.