Redi ad inferos, Satana!
The important thing you aren't mentioning is that Sony makes over $90B in revenue and over $7B in profits per year, plus have a ton of valuable assets.
These are some of the main reasons of why Sony is valuated over 50% more than Nintendo.
If desired they could sell something and get rid of the debt or get more profit in the short term. But they don't, they prefer to invest in the long term to have in the future higher revenue and profits.
As an example they announced that will sell around 80% of their Financial Services this fall, and said that will spend this cash mostly on acquisitions mostly for their entertainment divisions (not in getting more profits or getting rid of the debt).
I'd say that with GaaS like Smash Bros, Mario Kart, Animal Crossing or Splatoon they already have enough.