That's exactly it for me. Once I get a few bookmarks in the list, I'll inevitably need to organize them, but then I'll find I don't want to take the time to do that, so I just don't bother saving the bookmark.
At the end of the day, I just want to dump all my links somewhere and be able to find them again. I don't want to think about where they should go.
I built a journaling app recently [1] (the UI is similar to twitter, but for your personal thoughts), and what I've ended up doing a lot is dumping links in there. What I've found that helps is writing a quick note and adding tags, but even more than that, having a link preview generated makes it easier to remember what the link was later. (Based on screenshots, it looks like Grimoire is also generating a link preview.)
The fact that the journal UI is a "feed" also means I can browse through my history and see when I saved the link, so it has a chronological aspect to it as well. I think having all these affordances for finding things (commentary text, tags, link preview, chronology) is way more useful than hierarchical management.