All these companies still have their original core competency: Canon still makes optics, Brother still makes home equipment like sewing machines, and Nintendo to this day has not discontinued their playing card products.
Yes, you can buy Nintendo playing cards. I have several sets both modern and older and they’re very good.
These companies think in terms of decades and half-centuries. They may fall trap to occasional trends, but they’re not the ones who rush into a market to innovate; Canon started making a clone of a Leica camera and happened into doing the first indirect X-ray system in Japan, as a single example.
Lego's original core competency was toys, but not plastic ones. The original Lego toys were nearly all wooden, but they gained success with the plastic bricks.
It's unfortunate how many spinoffs they've had that failed.
[1] https://business.time.com/2012/07/23/innovation-almost-bankr...