North Korea has wanted a peace treaty for some time. E.g. 2016 Rand did an analysis on North Korea wanting a peace treaty to get the US to withdraw from South Korea (https://www.rand.org/blog/2016/05/behind-north-koreas-bid-fo...). They wanted a peace treaty under Kim Jong Un's father as well (https://www.reuters.com/article/us-korea-north/north-korea-c...).
Everyone seems to be forgetting that the reason that WE have refused to sign a peace treaty for decades is because of the human rights violations in North Korea. I have no idea how the narrative switched to North Korea wanting a peace treaty as a concession from them.