I managed to get lost there. An incredibly nice person stopped and asked in English - I’m a tall white person - if I needed help and insisted on walking me to my exit, several minutes out of her way.

I love Japan and traveling around there is easy.

Shinjuku station is a special case because it is so huge.

More precisely, the problem is not the train/subway station part of the station, that part is surprisingly easy to navigate. The problem is when you leave the station. There are 200 exits, and there is a good chance you end up in a place you didn't expect.

It's definitely possible. Try meitetsu station sometime. It's directly adjacent to the sprawling monstrosity that is Nagoya station (where it's also easy to get lost). Not only does it use a different, color-coded system of notation than other stations I've seen, trains stop at multiple platforms unlike virtually everywhere else. Consequently there are places where multiple signs are visible giving you different directions to the same train.

I also found in my recent two week vacation that it was easy 99% of the time, thanks to good signage and Google Maps. But I did miss one sign in a way that was difficult to recover from; if my partner hadn't noticed it I might have gone pretty far before I realized my mistake.

You should try going to Shinjuku with the Oedo line and change to the Odakyu line, it's an experience.

I take it you've never been to Nagoya?

OT but since multiple others are mentioning Nagoya: what's the best place to get some sweetened miso in mayo bottle thing(the tsukete-miso) around or inside Nagoya station?

I mean, I'm guessing I can just buy online, but it's something Nagoyans refuse to admit that every household in Nagoya/Aichi has one despite all having one in their fridge. It's almost strange there isn't an akafuku and kakete-miso bundle package in souvenir shops.

Osaka makes it possible.