Asked what he thought had driven Sony's decision to not include a physical drive, Pinello said: "I would say it's one of the more surprising decisions that they made, given their history with being on the forefront of media transitions like they have.
"So I don't know, I think it's a really great question, I'm not sure."
Instead of using a 4K Blu-ray drive, the PS4 Pro provides its 4K content via streaming, with an Ultra HD Netflix app already promised for the console.
Streaming is the future
Pinello's comments came in a wide-ranging interview with TechRadar, which also covered Project Scorpio and the end of the console generation.
When contacted for this piece, Sony declined to comment.