Looking at their equipment (wrapped puttees, LONG rifles, local dependence on supplies instead of prepackaged rations) and tactics (banzai charges against machine guns, minimal artillery), I still think they hadn’t learned a lot from WW1. But then, as Nomonhon demonstrated in 1940, they were very good at conveniently ignoring unpleasant truths.
I think their primary advantage in 1941 was that they had been fighting for five years already, they were up against comparatively modest and quiescent colonial armies that couldn’t be resupplied or reinforced, and they had the advantages of surprise and years of planning. Of course, even that didn’t always help them, as General Homma learned the hard way with the Bataan campaign.
Their biggest failure, of course, was that they had planned on a quick conquest of the resource-rich Indochina and Malaya/Dutch East Indies region, which forced them to take a lot more territory (i.e. Burma, the Philippines and Central Pacific islands) as buffer zone. Not only did they manage to overextend themselves, but they got drawn into a long, logistically-impossible-to-support war, which was the last thing they were prepared to deal with.
That is true that like the Axis in Europe, their military was geared to a “blitzkrieg-type” war, fought for a short time over short distances. For both of them, were bled dry by conflicts that dragged on longer over greater area; while the Axis was slowly ground down in the Soviet Union, Japan at the time of its surrender still had over a million troops tied up in China (and came nowhere near defeating it).