I hate to say I told you so, but I did. The reason cited for the halt in production is none other than slow sales. My favorite quote from the Gamespot article is this:
“The PSX’s controls were being developed by the games division, while the Blu-ray Disc division was doing the AV parts. But the divisions couldn’t work too well together. As a result, the capabilities of the PSX became incoherent, and it ended up as a machine that’s neither a game console nor a DVD recorder.”
Source: Gamespot