A text file(s) with a list of links. Use LibRedirect or some other redirector extension to redirect the links to the instance of your choosing, just change the redirector when you want to change instances.
Also- Couldn’t you add ‘groups’ to your current setup by just creating folders in your existing bookmarks? (assuming you’re using bookmarks that are baked into your browser)
FR, younger generations don’t have to fix anything / solve any problems on their PC; any problem they’re likely to run into is an abstracted error within Google Docs, within their browser.