I’m not sure what you are concerned about in particular in the context of traveling to these places. I have lived in Korea for over 12 years, so I will share my two cents.

In another comment someone has said this:

Both countries have highly invasive laws and will demand access to many things.

In all my time living here, I have never ever had the government “demand access” to my things, and I have never heard of this happening to anyone traveling here. In the times I visited China, however, ALL of my things were ALWAYS searched at the airport (plus telecommunication itself is just a fucking nightmare there). Even going to Japan I was always flagged for extra searches, but never Korea. I am not sure what they mean by “demand access” but I think they have overstated a bit, or don’t really know how it is here. If you commit crimes while you are here, then of course, like pretty much the rest of the world, you can expect to be interrogated, and depending on the nature of that crime, your stuff could get seized and searched (but it is not the case that any run-in with the cops will result in them cloning your hard drives or anything like that. There is a lot of red tape around that, so unless there is good reason to do so, no one will go through the trouble).

Korea does not have great laws about privacy, and people are mostly ambivalent about it. The main “privacy-offending” thing about Korean digital culture is that your citizenID is linked to your online accounts (not all of course). So, if you have a blog on Naver, you can be anonymous to readers of that blog (as in you can use whatever handle you like), but if, for example, you are doing illegal things on that blog then the police can easily identify you. For a foreigner visiting here on tour, this is all irrelevant. If you register as an alien (for work or study etc.) then you may end up making accounts here, but you are not really obligated to…and it is not the case that ANYTHING you do online must be tracked by the Korean government or anything like that. I have blogs, gemlogs, phlogs etc. scattered all around the internet. The Korean government will in no way seek those out to surveil me, let alone try to control or censor what I do there. Their operation is just not that focused, and it is out of their jurisdiction anyway. It just doesn’t work like that. Of course, if you break laws here, then expect to be investigated. But there is no law saying you cannot have overseas accounts or whatever.

It is not the case that everyone is constantly subjected to 1984-style surveillance and totalitarian oppression. If that is what you fear, then don’t go to China. As far as surveillance goes, I would say Austraila is actually worse (based on what I have gleaned from the news). Overall, the main concerns I have about privacy here are the same that apply everywhere: apps, services, operating systems slurping up as much of your data as possible and selling it etc. However, Korea has adopted GDPR-esque laws that require Korean companies to notify you when your data has been provided to a third party, or requested by the government. If you are just visiting, you probably don’t really have a reason to sign up with Korean service providers, and in some cases you will not be able to unless you have a visa (other than a tourist visa).

If you are worried about your internet browsing being surveilled, don’t be (like I said, it is not much different from most other places in the world). Some sites are “blocked” by ISPs, mostly porn sites and North Korea propaganda sites, but this is nothing tor cannot circumvent. There is no “great firewall” like in China, and in fact, the blocked sites can all still be accessed by using a DNS provider other than the Korean ISP itself. But tor or a VPN is the easiest way. VPNs are not illegal, tor is not illegal. No one gives a shit and most people don’t even know what these are.

There are CCTV cameras all over the place, but the vast majority of these are not involved in facial recognition or anything like that. There are some of those in place out in the wild, but they are actually pretty rare and controversial. To me, the main problem about privacy here is that people just don’t even think about it. So for example, when COVID first hit, the government was providing data to the public about where infected people went (not their identities but their movements). So there were cases where some wives found out their husbands were visiting brothels, etc. It was a weird lack of oversight that resulted from the general ambivalence about privacy here.

I don’t know if this helps at all. If you are considering visiting here then I recommend that you do. Korea is a very interesting place, and usually people who visit kind of fall in love with it. As far as privacy is concerned, it is nothing like China at all. Although, I also recommend visiting China just because it is a fascinating place too! If there is anything in particular you are concerned about privacy-wise, let me know and maybe I can give you some perspective on it.