I get that question often when presenting my deck loaded with impressionist paintings to a big corporate. Serious companies cannot make presentations like these.

Wrong. Visual presentations without bullet points can be highly professional, and highly serious. Just take a different theme than impressionist paintings.

Right. I do agree that being serious adds a design challenge. Everyone can Google image search a bunch of funny page-filling images together and add some outrageously big wacky fonts to them and call it a visual presentation.  The challenge is to add some aesthetics, but it is an easy step to make once you have made the big leap of leaving bullet points behind.