1) These fans, whosoever they might be, would be idiots. People aren't picking their console primarily for size of the box. That's a far lower priority concern than price, library, performance, etc. 2) If MS can remove the optical, so can Sony and compete directly.Well one reason is size. Sony fans have stressed that the smaller ps4 is a huge sale factor over the larger xbox one.
What MS can offer is cross-device compatibility via the Windows ecosystem. Everything else Sony can go toe-to-toe on.