Sony's always had a very weird obsession with proprietary storage media. I think they resent the licensing model of CD-ROMs (essentially none) and desperately wanted formats they owned and could license out. At the same time their entertainment division would want to hamstring those formats with onerous limitations or DRM.

The end result was Sony always seemed so schizophrenic with storage formats. They'd come out with a format that looked cool on paper but then have some artificial limitation (including stupid prices) that made it unattractive.