Bookmarks for me are mostly useful as quick links to highly "dynamic" sites (like HN), where offline snapshots are less useful, or for massive sites that are not quick to snapshot, like Wikipedia (an offline snapshot of Wikipedia is definitely useful, I just don't think the browser is the right tool for that).

For long-form content that I want to come back and read later, I find Wallabag is quite good. For making snapshots of large websites I use Kiwix.