it seems to me that the most popular korean dishes tend to be focused less on finesse and more on some sort of excess or intensity of flavor vs. the balance that tends to characterize other asian cuisines., but more diverse, i wouldn’t think so.
FWIW korea is slightly smaller than britain in terms of size, the point being you have less chances of having the same diversity of terrain and climate that china has - you have less different ingredients to start with. but korea is also one long peninsula, so most of korea is a lot closer to water so one could reasonably expect that seafood makes up a larger percentage of their overall cuisine, etc.
OTOH, you have the uniqueness of k-town which has been described as being a district of seoul in both terms of capital and culture - some suggest that soontofu originated here and became popular in seoul. i suspect some sort of cross pollination is going on - here they’ve assimilated certain western ingredients like mayo and cheese which go into the cheese corn you can find in k-town bars… then you’ve got the war and the UN presence leading to the development of dishes like budae jjigae, etc. whereas china (with perhaps the exceptions of HK (the british) and shanghai (the international settlement back in the 30’s) has remained largely insulated from western culture. i wouldn’t go as far as to say that those are definitive factors but it’s worth nothing IMO that in some ways, they’ve had access to ingredient and cultural sources china does/did not.