Call me old-fashioned, but I use Cmd-D to save bookmarks, and either the search bar or the bookmark library to organize/look through them. When I decide I want to blow away my operating system, I export my bookmarks and import them at the new incarnation.
The problem is link rot and searching contents for me
How do online services solve link rot?
As a service user by archiving a copy of the page. Or via internet archive
Internet archive is possible with regular bookmarks too, using extensions like web-archives, allowing you access the archived version in a click.