Will it help build street cred with your cohort? Yes.

Will it help you deal with crushing work, zero appreciation, and zero sleep?
Yes.

Will it help you get into the GSD?
Probably not. You're evaluated on design work (which you won't perform at any Japanese starchitecture internship) and SoP+references. Maybe you can get a recommendation from an associate or even a partner, but most likely, you'll be another anonymous intern drone stuffed away in the intern barn.

Never take an unpaid internship... regardless of who's name is on the office door.

unpaid internship at sejima or similar is not on the face of it a bad thing. I am setting aside the logic of pride and professionalism that gets some people really worked up, not because I disagree but because if you are thinking about it it means you are after something else, perhaps a road less traveled...

Working as intern here seems to be the luck of the draw whether you get stuck making paper chairs for 3 months for an exhibition in MOMA, or if you get to do the models for a cool competition that will change the world.

We have taken in several interns after they worked at a Japanese starchitect for a portion of their planned 3 months. They quit because of bullshit or burnout and we heard a lot of stories as a result. Shigeru Ban is not one of the offices we heard a lot of bad things about. The only thing that comes up is that he is reportedly overworked and it is hard to get his attention sometimes, but he is the decider, so thinks move or stop on his word.  That might have changed since he won the pritzker. He seemed nice the few times I met him (he is professor at my university but I never taught with him) and does interesting work with the students that I admire.

Compared to an American or European starchitect offices the Japanese office is entirely unprofessional and wild. This may be where the creativity comes from but it also builds a lot of frustration if a person is not flexible. The fact that frustration is accompanied by almost no pay makes it a crazy situation.

To answer your question, maybe. Maybe it places your background in a different category in some way.

More important, is it something you want to do? As a personal experience I do think travel to another country and working in a place that is seriously devoted to architecture as a lifestyle (again, different from most Western offices), can be rewarding. Being in a culture filled with apparent non-sequitur events on every corner is always something a person should do. If you are lucky you can do that by working in the carnival down the road. Or you can do it in Japan, which is also cool. If you need to justify the experience as an investment in university applications I wouldnt do it. If its something a bit deeper i would definitely think about it.

Tokyo is awesome city to live in btw.

I think most grad school require more than just a statement of where you worked.  If you work there and are able to get a recommendation letter or use them as reference, then it will surely help for your application

Just like what Dangermouse said, getting into GSD is predominantly portfolio+recommendations, with a little bit of SOP influence. It will definitely help as long as you get a recommendation letter from Shigeru Ban himself, but I'd assume that would be pretty difficult.

Personally, working for a few years before going to grad school is not a bad idea. It will open up new perspectives you will never get when you're fresh out of undergrad. I sometimes wish I hadn't gone for my masters right away if I ever had the choice. Waiting another year working with OPT to see how your visa issues turn out doesn't seem like a bad idea. Although I've been away from the country for quite a while, and have only vague understandings of Trump's visa policies.

Figured I'd chime in for posterity.

Had a friend with an incredibly banal and unspectacular portfolio that which got accepted into a chinese starchitect firm. Nothing to crow about tho, figures they needed extra hands at dirt cheap costs. Then again we're talking about chinese here so that's a different can of worms altogether.

Japan however seems like a nice place to even explore for an extended period of time. Certainly is a good thing to broaden one's horizons whilst indulging in a contrasting work culture.

Nevertheless, do make an informed decision before moving forward.

not to make it sound bleak, you probably cannot control what you get out of the internship. Unless the project is for an overseas client, and really event if it is, what you will likely be doing is model building and other grunt work, pumping out variations for someone else to consider. 3 months in a place where the language is not (oh, so very not) english means you are illiterate and kind of incompetent by default.

This doesnt mean you shouldnt do it, nor that it wont be awesome, only that you are starting from a weak position and it is important to know that going in.

one other point (as someone who gets portfolios every week with this problem) please point out what you did on the project. When quality of work goes up by 300% because Sou Fujimoto is guiding the work don't  forget to include your role. I have decided to treat it as plagiarism when it isn't pointed out because its just too absurd otherwise. Portfolio in the bin, end of story. Amazing renderings of a 300 million dollar project that you did half of a model for is not honest. It is really hard to document that kind of work but the effort is appreciated and there are no problems with expectations later on about how awesome you really are.

It probably will help get a job later on.

 

I'd look at an application twice over if it had Shigeru Ban on the resume.

Definitely more attractive than a random small town architect if you're hoping to work in a place like NYC or LA.