Just for the record, I don't think that South Korea is particularly cheap. As OP demonstrates, one can live there for USD 1000/month, but that really holds for most countries. While the US is in the top 5% in terms of nominal GDP per capita, South Korea is in the top 15%. For cheap, yet comfortable and safe, I'd aim around the median, eg Indonesia or Georgia.
ETA: Nomadlist suggests €1,925/mo for Seoul, €1,530/mo for Jeju Island, South Korea; €1,047/mo for Tbilisi, Georgia; €627/mo for Bandung, Indonesia.
ETA: Nomadlist suggests €1,925/mo for Seoul, €1,530/mo for Jeju Island, South Korea; €1,047/mo for Tbilisi, Georgia; €627/mo for Bandung, Indonesia.
ETA: Nomadlist has a list of places below USD 1000/mo: https://nomadlist.com/places-on-a-budget