Its amazing how certain memes get started and despite all evidence to the contrary, become instilled. One of those memes from WW2 is that the Japanese were without armor during their conquest of large parts of the Pacific.
The Type 5 was not only adequately armored to deal with enemy infantry but was also quite capable against the majority of armored vehicles found in the region to include the US' Stuart Tank. To top it all off, it was truly amphibious.