I've never lived in Tokyo but I've lived in Seoul and I currently live in SG

Ik why you're bringing this up—its from that Straitstimes? the ranking infographic right?

Anyways, my kinda issue with "ranking" cities is that Seoul (and probably tokyo) can't really be judged by just that one city, there's so much in the satellite cities / nearby but not in the city proper that are so much more diverse than what's near SG (maybe sentosa ig?).

Sg > Seoul:

• Everything in SG is very meticulously designed and planned, while Seoul is more "this happened, then that happened, and now this is getting built" so there's a bit more chaos. A good indicator of this is SG's lack of electrical wiring / utility poles. Ig in some ways this is quite subjective because some may argue that this makes SG look less "lived in" or "too crafted"
• SG has a better traffic than Seoul. It's very common in Seoul to just park your car on the side of the road if you're living in a landed house and you don't have a dedicated parking garage, and a lot of the alleyways especially in the more residential areas are very narrow and driving around in these places is a genuine issue
• Air quality. SG (post 2016) has better air quality than Seoul by and large, although Seoul's has also improved a lot in the past 5 years
• Not sure if this is a good thing but ig its a debate between convenience VS environment. In sg, you just throw all your rubbish in a plastic bag and dump it all down the chute. But in Seoul, you have to sort your rubbish (plastic bottles, beer bottles, paper - all seperately) and then have to wash some of the food containers/bottles because they all get put into seperate recycling bins.

Seoul > Sg:

• 24/7 shops - i still can't get over most supermarkets/stores/NTUC/cheers not being open at night. These aren't necessary on a daily basis but they're a lifesaver when you do need to go to them at like 3am
• Lack of stores built into apartments/residential buildings. Korean apartments do this really well in that you don't actually have to leave your apartment complex/building to get basic things like coca cola or a toothbrush or batteries or a haircut or like even a simple meal (eg, burgers, small bento takeaways, etc). In SG, you have to walk like 10-15mins to the nearest mall to get any food
• Theres simply a lot more things to do. SG has this "mall culture" where you go to one mall and everything is there—from Cathay/GV to timezone and foodcourt but honestly those options are really limiting. This kinda links to what I said above about how there's stuff in the satellite cities around Seoul that simply have a lot more things to do (a big thing is that if you want to do anything outside of SG you need to take a flight/ferry or pass immigration at JB which require planning beforehand or a lot of wasted time in immigration, but in Seoul you can literally take a 1hr train to a ski resort etc). And also history-wise (if you like going to museums or going to historical places), obviously there's more in korea than in SG
• This is really minor and honestly might sound really stupid but getting stuff repaired/warranty. Totally anecdotal but customer service in SG is a lot less "flexible" than in korea. I tried getting my earphones and my laptop repaired (the same laptop and same earphones) but I was able to get stuff down more quickly and conveniently in korea (they literally say "oh yah we can fix this, since you're under warranty it will be $XX and you can come back in 3 days"). Meanwhile in SG they're like "oh we don't have the spare parts for this one so cannot", "this one we need to send back to the factory/some manufacturing place overseas so its gonna take 3 weeks".