I agree with you. The person in the article worked at Mercari which I used to go their tech meetups. The moment you entered it was as though you teleported into an SF/SV meetup. Mostly English speaking people with English presentations in a room with an SV like microkitchen, free SV snacks, etc... That's not the norm at all.
Yeah, saw Mericari and had some flashing lights go off.
Most Japanese tech is in - well Japanese - companies like Mericari, Woven and Rakuten are exceptions, hence you get a blog post on how to speak English properly.