As search engines have gotten better over the years, I find my use of bookmarks is usually write-once read-never.
Part of that is due to the fact that iOS is now my primary consumption platform, and finding bookmarks in a complex structure is much more awkward than it should be.
Part of it is just laziness: trying to manage a complex bookmark folder is more work than I care to do when search engines give me 99% of what I need.
For what it's worth I had the same problem with folder/hierarchically structured bookmarks, but tag-based bookmarking (like del.icio.us used to provide) meshed very well with me and my workflow so I wrote https://savecrate.com (still a WIP and rough around the edges but functional enough to work for me)