Talking to IGN, Yoko Taro, the creator of Nier Automata, commented on the subject. When asked if there was anything in the Korean game Stellar Blade that Japanese developers couldn't do, the developer said that they can no longer keep up with the West when it comes to technology.
For Yoko Taro, Chinese and Korean studios have found it much easier to adapt to Western tools, such as the Unreal Engine, which has allowed them to make a greater leap in technology:
Yoko: I wouldn’t say that we’re not able to come up with it, but we can’t keep up with the level of technology anymore. Stellar Blade is of a really high technological level, to the extent that I’m looking forward to seeing how Western gamers will react to it. NieR: Automata’s camera was from a pretty far-off angle and it wasn’t of the same standard as high-profile Western games. In that regard, I think that Stellar Blade has crossed a big barrier. The quality of not just the characters but also the environments is also on par with Western games. I’m honored to hear that you were inspired by NieR: Automata when creating Stellar Blade, but I hope that in the future we can see Western games inspired by Stellar Blade.
For Yoko Taro, Chinese and Korean studios have found it much easier to adapt to Western tools, such as the Unreal Engine, which has allowed them to make a greater leap in technology:
Yoko: Japan found success with not just games, but also anime and manga early on. After being exported to the West and other Asian countries, games, manga and anime have evolved in their own ways in each region respectively. As for games, it has proven difficult for Japanese companies to implement Western systems. Japan has a long history with companies developing their own engines, and it was hard to move away from that. We were very late with incorporating rendering tools and middleware from the West. Even to this day, many schools don’t teach this to new developers. I think that Japanese people are not good at adapting technology from overseas. Chinese and South Korean games were much faster to use engines like Unreal for games with a Japanese aesthetic.”