I've got little idea about other Jap engines, but I know the Peugeot engines hit well above their weight for many years. The XU9J4 of the 1989 Mi16 had a 1.9l 16v and produced 160hp/119kw in Euro spec, but was detuned to 145hp/108kw when it landed here. For a early-ish engine this was a phenomenon at the time and had nifty 8-2-1 headers, though it did suffer from remarkebly poor torque below 4,000rpm.
This all changed when the XU10J4 of the S2 Mi16 and 306 S16 came out in 1993. The 2l engine pushed 116kw/155hp with 194nm torque in a wide band. The torque was achieved with a dual intake manifold system which swapped around depening on revs and throttle. I had the S16 and it was a really stong engine, though a little flacky on the longevity of the vacume actuators. Notice the heat glue on the left hand actuator
What's being missed is that high specific power comes from high revs, while high torque comes from maximising flow efficiency in the rev bands needed, mostly archieved through tricky intake systems not able to flow enough to give good specific power. I believe that the Honda engines are still a compromise, favoring heaps of revs and little torque.
Take the new Renault Clio 182 (2.0l)as an example, Maximum torque 200Nm @ 5250rpm and Maximum power 131kW @ 6500rpm
Compared to the new Honda Integra S (2.0l)
Maximum torque 194Nm @ 7000rpm and Maximum power 154kW @ 7800rpm
Sure, the Honda has more power but a huge revs and that's achieved by pushing the peak torque way up to 7,000rpm. Assuming a flat torque curve it should be pretty close to, if you scale the Honda engine back to 6500rpm it would produce 128kw.
By no means am I discounting the Honda, they are and always have been of recent time a brilliant engineering feet, just that they need revs to creat their huge specific power...as do F1 engines.
At the end of the day though, boosting gives you the best of both worlds though.
