I found a neat interview with a couple Japanese game producers, who explain the differences between their country's games and Western games and why they think that's the case. While it seems to more centered around modern games, I think a lot of it applies to older games like Mario vs. Keen. Check it out:
https://hg101.kontek.net/eastvswest/eastvswest.htm
East vs. West: Interview with Keiji Inafune and Hiroyuki Kobayashi
East vs. West: Interview with Keiji Inafune and Hiroyuki Kobayashi
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