you had a lot of local knowledge
There's local knowledge, and then there's basic research and preparation.
I've been holding off on commenting further on this thread, because I happened to spend seven years at uni in Tokyo and am fluent in the language, and part of me does assume that someone fluent in Norwegian would find better places to eat in Oslo than I'd be capable of and so on.
But I spend about four months of the year in a pretty expensive part of Tokyo that's home to a multitude of embassies and lots of expats who speak not a word of Japanese.
Ruling out your non-preferred Japanese cuisine, just some of my local lunch options in the 1,000–1,800 yen range (mostly towards the lower end) include:
Mexican: Soup, salad, choice of one from seven mains, coffee
Indian: Salad, rice, naan, three small curries, lassi/coffee (+500 yen to add some tandoori chicken and some lamb)
Italian 1: Excellent pizza + excellent coffee
Italian 2: Soup, salad, bread, choice of one from three mains that change daily, small dessert, excellent coffee
French: Soup, salad, bread, main, dessert (add 500 yen to have two mains, one meat, one fish)
Thai: Salad, rice, choice of one of eight mains (under 1,000 yen)
Korean: Fantastic set of ten tiny appetizers + one main dish, option to add on a 200-yen beer or cider
And there are three dine-in bakeries with decent coffee.
And three very decent hamburger joints.
And one truck that does nice toasted sandwiches.
This is less for your sake, Renato (as a man who obviously knows what he likes and what he doesn't), than for others who might hit this thread because of the title.
The vast majority of people will not come away from Tokyo disappointed by the food.