My understanding is that the increased structural costs and weight penalties associated with the Ocean series combined with a more limited target market were deciding factors for the series.
The European charter market demographic with its requirement for multiple cabins was significantly greater than the cruising-couples-desirous-of-a-40-foot-two-cabin-design market. That seems a reasonable explanation for the short duration of the Ocean series.
I find the Ocean 40 to be a sound and quite comfortable boat for a couple and I think it offers good value for money. I'm very happy to own one.