The first K-drama I ever watched was a modern spy thriller. But then Netflix streamed a historical K-drama and I realized how ignorant I was about the history of Korea. I find it fascinating.
My initial complaint was that streaming sites did not have enough Korean dramas. But that's not my complaint anymore. I can find K-dramas almost anywhere these days. I have noticed that many of the series I watch now are mixing in the events in historical or ancient kingdoms with the modern republic. Characters are traveling through time. I like the "mix".