There's other problems. Of the things you've brought up Yakuza and MGS5 are the only one I can't immediately excuse away on incompetency grounds. RE6 was a disaster. To port that turn they'd need to pull a Realm Reborn/Razor's Edge. Revelations was well received, in fact porting it is probably to cover up for RE6 since Revelations is a significantly better game. Likewise, Lightning Returns looks rough, I'd have a hard time believing that game won't be rushed and isn't experiencing development problems. Dark Soul 2 is more interesting but From is a small, technically incapable developer.
More interesting is that all the big titles are not next-gen. It seems reasonable that they'd want to stretch this party longer given the big install bases but how is that going to reflect on next-gen systems especially without BC? This seems a lot like the Vita situation.
RE6 sold about 3x more than Revelations, and Capcom bought themselves a 39/40 in Famitsu afaik - so I don't really see how one would be a much better porting decision - other than that the main source of sales for the series has already been tapped for RE6, so they don't see much point in porting to the Wii U.
Yes, technical proficiency could be used as to reason away the silence on the Wii U, if this was a technological generational change rather than simply a chronological one.
It wasn't just HD gen, Japanese devs are notoriously slow to transition in every cycle, which is why I listed the previous gen also. It was the same before that, with most major publishers still focusing on SuFami in 94/95 before eventually deciding to move to PS1 in 96/97.
I agree the lack of ports announced for Wii U is worrying given it's technology positioning, but it was the same thing for Wii initially too, and even Vita last year really. It might never really rurn around like the former, or maybe Nintendo can incetivize their way through it like the latter. Wii U 3rd party announcements in general have been pretty bizarre in how they're handled the whole way through, for every region.
As far as the lack of comparable announcements versus PS3 (or PS2 before that), that's the difference in following up a clear market leader versus not. The only system this gen with PS2/PS3-like early commitments out of Japan is 3DS, in large part because it's the successor to the clear market leader there last gen. If we examine PS4 under the same microscope versus PS2/PS3, it's also lagging significantly. Do you then also expect PS4 to get significantly less Japanese support than PS3 did?
"Normal" generational transitions provide technical hurdles. The Wii U, however, offers comparable performance and has been touted as easy to port to from the 360. It's not a transition to 3D, there's no Cell broadband engine, it's not purportedly difficult to work with like the PS2, there isn't anything like programmable shaders to get a grip on.
The PS4 was announced 54 days ago.
The Xbox 3 is unannounced.
The Wii U was announced 679 days ago. And has been released for 129 days. There have been two E3s, two TGSs, two GamesComs and two VGAs since the announcement.
There's more leeway in terms of waiting for announcements when the system has just been announced, and its expected multiplatform companion has yet to be announced. Even then, we've already been told something Final Fantasy is coming at E3 - please be excited, and Capcom have signaled support with Deep Down. Again, the FOX engine wasn't created just to make PS3/360 games for Konami. Even Level-5's Hino has already said they're planning a PS4 title; I'm not sure if they've given any indication of making a Wii U title as yet.
Looking at the Western market for a moment, we have Battlefield 4 also not announced for PS4/Xbox 3. Something that has already been tacitly confirmed.
Wonderful 101, Bayonetta 2, partly Shin Megami Tensei X Fire Emblem, most likely those other hinted collabs...
Are not third party support.