It's also the OG kimchi as Koreans didn't have red peppers until the Columbian Exchange (but have been preserving vegetable via brines since the Three Kingdoms era)!
If you can't eat normal kimchi due to spiciness, there are variants of kimchi that aren't spicy and resemble sauerkraut or doesn't even include cabbage at all.
If you make your own sauerkraut, or anything else fermented really, the flavour is much more complex and varied than the store bought stuff.