Who said that knowledge is gold?
Considering the time you spend online, it appears that you are building a digital wealth. For example, on services like Quora or StackOverflow, you are truly building a online expert, who can be recognized by thousands of followers and build strong relationship with some.
Contributing to coding projects, as your GitHub account enables you to do, also makes you an expert in a field where only a few people are experts. Consider the code you might have left on GitHub. Do you want it to be part of your online estate?
In all these case, you have been building an identity that made you a reference as well as a network of relationships. You’ll have to spend some time to think about the becoming of these assets after your departure. Do you want to close the accounts, erase your information, or let it be for some time accessible to everyone looking for knowledge?
You’ll have to be sure to write clear instruction the the becoming of your social network accounts. They can be deleted, left as a memorial, or curated : it’s up to you.