The book "I'm Dead, Now What" is a hardback, paper book with a wire binding. It has many pages for filling in information about handling a death. One problem I can see is that pages of passwords or other information that changes cannot be easily updated. I am confident that there are other problems.
I just Googled "after my death, can my wife use my bank logon and password?" I realize that her fingers can tap on the appropriate keys but I don't want her arrested for breaking some law about notifying institutions about a death. I am not nearly as used to dealing with a death as is the funeral home or crematorium. They are obligated to notify certain authorities as is a hospital, I imagine. The answer I read said that if both of our names are on the account, there should be no problem.
My wife was the executor of her mother's estate. It was a complex job even though her mother basically died without property or funds. Either of us might be the executor of the other's last will.
A few times recently, I have experienced an account at an online business or bulletin board being closed after an extended period of no use. That might happen to social or information accounts that aren't of interest after I die.
I was surprised at the number of books of advice and of pages for recording information that may be important in handling a death. "I'm Dead, Now What?" is definitely not the only possible choice. Like seeing the doctor, reading a book that you don't want to read and other chores with built-in reluctance, preparing to handle a death can be a drag. Still, it may be better to work on the related task of information gathering and organizing before it is really needed. That way, there is time to learn and re-learn.