The answer is yes and no. Hiroyuki Agawa, a former IJN naval intelligence officer turned naval historian famously quipped "the three greatest follies of the workd were the Great Wall of China, the Pyramids and the battleship Yamato." Despite the vast effort expended in their design and construction, the Yamato-class had a number of defects. Their main guns were inefficient, the armor belt had defects, and the all-or nothing armor scheme made them vulnerable to torpedo attacks. More critically, the design possessed insufficient range and speed for a transpacific war, which is why they sat out the Guadalcanal campaign- they would have used too much fuel and be exposed to Allied airpower on the return to Rabaul/Truk. In hindsight, the resources would have been better spent on other ships.

However, the claim that Japan should have launched two-three Shokakus for one Yamato is problematic. Japan had very limited industrial base that imposed enormous bottlenecks on its wartime industry. Although having another Shokaku around would have been useful in 1942, the slow pace of aviation production and the patchwork expansion of the IJN's training of aviators would have meant that such hypothetical carriers would have lacked the planes to put on them or the personnel to man and maintain them.

The dilemma of the IJN was that they had lost the war with the US as soon as they embarked upon it. Evans and Peattie have a shocking statistic that if the IJN had managed to sink every major USN vessel on 7 December (both Atlantic and Pacific), suffered no major losses in its campaigns, and completed its overly optimistic building plans, the IJN would still be an outnumbered force by mid-1943.

Sources

Agawa, Hiroyuki. The Reluctant Admiral: Yamamoto and the Imperial Navy. Tokyo: Kodansha International, 1979.

Evans, David C., and Mark R. Peattie. Kaigun: Strategy, Tactics, and Technology in the Imperial Japanese Navy, 1887-1941. Annapolis, Md: Naval Institute Press, 1997.

Peattie, Mark R. Sunburst: The Rise of the Japanese Naval Air Power, 1909-1941. Annapolis, Md: Naval Institute Press, 2001.

I need to dig into my sources but I did quite a lot of research into Naval Intelligence.

A lot of people would raise the question (more generic than yours but still related) that why major naval powers kept producing large battleships when Naval Air Power advantage was proven rendering battleships almost obsolete. The US for instance kept developing and producing several units of the large Iowa Class.

There was 1 thing though in the thinking of the time -the 1 I need to research - but long story short is that there were few aircraft carriers in service and Midway proved that a significant part of them can be wiped out with successful air strikes, should this has happened and both sides got their carrier force reduced to levels too small to make an impact in the war, what are you left with to ensure naval superiority? Battleships.