I had to manage my parents estates in the early 2000s and my experience then was that the digital companies had very little experience or idea of how to deal with estates. Some simply asked for a copy of the letters of estate, others made it extremely difficult. Can’t imagine what the current crop of social media businesses will do.
I update letters at the end of each year to loved ones (spouse / kids / friends / parents) and I update letters at the end of each year to business contacts (have my lawyer review them as well).
iPhone now with 15.2 makes it super easy to designate a legacy contact --> https://appleinsider.com/articles/21/12/14/how-to-set-up-leg...
I also am prepaid on Office 365 for domains / email, AWS hosting / and iCloud backup (with family sharing settings) for the 3 years out. So when I pass, well then after the initial grief there's no immediate need to update anything for 24 months. Plenty of time.
"I am not afraid of death, I just don't want to be there when it happens." - Woody Allen
Do not share passwords for investments/banks. This is against TOS for most financial firms, and someone logging in to your account after you die and making changes is a big problem. Financial institutions have procedures for dealing with death and distribution to beneficiaries.