Workflows can be shared either by creating a workflow.is link or exported as a .wflow file using “Share as File”. Using the latter option, I’ve set up a GitHub repository of workflows that I’ve created. I’ll be regularly adding to the repository so it’s a handy way to always have a copy of the workflows I create.
Alternatively, you can simply download a ZIP archive of all the workflows. I’d recommend cloning the repository as you can easily keep it updated whenever I add new workflows.