Here's your answer:
Groups and artists are trying to ensure the timing lines up with the US Billboard charts. You can say that 'placing top 10 on bb200 albums chart which doesn't hold that much value in recent years tbh' but that's just pettiness talking. It very much does matter from a financial perspective, which is why companies do it. And despite the melodramatic claims that "placing top 10 doesn't matter," it it still very few kpop groups that make the top 10 at all.
I'll never understand why people get butthurt about more kpop groups succeeding outside of Korea, in addition to inside of it.