Japanese failures can be traced to their pre-war thinking and assumptions and this was borne out in the weakneses they accepted in their aircraft designs. The Japanese gave unrealistic assessments prewar as to their own strengths, and assumed the western democracies were weak kneed and would not fight beyond a few months into the campaign. They placed considerable weight on the assumption the Germans would force the Russians out of the war in 1941, and that the Germans would swing back west to the west, leaving the Allies with little choice but to negotiate a settlement with Japan.
For their war strategy to have any hope of success, the Japanese had to deliver a killer blow from the start, and complete the conquests at breakneck speed. Upon achievement of the (assumed) defeat of the western allies and Russia in other TOs, the Japanese believed they would have time to consolidate, fortify and build up their positions with years of time up their sleeves. If, or more likely when, the allies returned to the field of battle, it was assumed they would suffer heavy attrition as they attempted to advance onto the vital Japanese interests.
Clearly the Japanese were wildly over optimistic and unrealistic in their thinking. The allies recover, the Soviets did not surrender and within 15 months the axis on all fronts were on the retreat.
Whilst the Americans did modify their Plan Orange strategies to take advantage of their new fast carriers, these were hardly the war winning weapons of war the Americans so often like to claim. By the end of 1942, both sides had fought their carrier fleets to utter exhaustion. In the case of the USN they were reduced to just a single operational CV in the PTO (which even then was damaged), the IJNs had 3 smaller fleet carriers but had suffered near fatal losses in air crew. What crushed the Japanese were the powers of recovery possessed by the Allies and their ability to simply overwhelm the Japanese defences. They did this with a multi pronged series of attacks, the most important being their submarine campaign. Next in importance was the unrelenting allied air sea and land campaigns fought in the SW pacific, the south Pacific, NW Australia and the CBI, which prevented the Japanese from replacing losses and building reserves, whilst the Allies were able to do just that.
US carriers did play a pivotal role in the final campaigns, but they were noticeably absent for most of 1943, as were the IJN carriers. They were a factor, but not a critical one. Mac had worked out strategies by early 1943 which did not require carriers (the socalled "island hopping strategies" and "wither on the vine"). By June 1944, the Japanese were facing defeat, and they knew it. Their entire efforts from that date until warsd end was about securing an honourable surrender not about any form of victory. In that last year the USN fast carrier forces were at last decisive as they moved at will in enemy controlled waters blasting anything that opposed them out of existence.
The Japanese retained their two principal fighter types, the Zeke and the Oscar in more or less original form because they had no choice. The pressure from the allies was relentless there was no time to significantly alter the design as had always been intended so the Japanese struggled on with aircraft design for offensive purposes when they really needed fighters for defensive purposes, fighters in which range and manouverability were second to speed, firepower and protection. For those of us with Japanese symathies, it is a sad account of history. For the rest of humanity including the Japanese themselves, it was a merciful omission that allowed the war to end quickly