I'd like to start by noting you're taking a publisher and comparing them to individual developers, but I'll humor this anyway.
Part of this is a the overall silence of Capcom and lack of announcements of games built on top of their engine that's going to power all their major PS4/XB1 titles.
If the issue here was just Deep Down, I wouldn't ask a question. They also themselves stated there were issues.
Well, that game lost its two creative leads, and the one guy we knew was in the game isn't anymore, so I feel we know why it's taking a while.
We're getting a beta for Halo 5 in December and releasing some kind of Halo 2 multiplayer upgrade on what they describe as "an Xbox One engine", but I'm not sure if that's actually the same one they're using for Halo 5. That said, for one studio, that would still be more games than Capcom.
I don't think there's much praise for their technology.
Dragon Age: Inquisition releases in November and has lots of footage. It has not mysteriously disappeared. They've also shown off snippets of three other games on the same engine, though it's clear they're pretty early.
The studio was downsized to 17 people while the rest of the staff shipped Need For Speed: Rivals at launch on the engine they're using this generation.
They do take quite a while to launch games. However, I don't think they've made any statements about tech issues.
I didn't state anything about other Japanese developers. Do you feel there are notable issues with other ones that made this pop to your mind?