> Afraid to close the page because they wont find it in their history or bookmarks? Is this more an issue with bookmarks and history not being as useful as they could be?

I think tabs are just the better user interface.

It's not that I'm afraid I won't find the page in my history and bookmarks, it's that I don't want to have to do that because it's painful. History is full of irrelevant pages. Bookmarks make me lose my flow constantly wondering if I should bookmark a page or it's not needed (and in which directory!).

Tabs have a very simple workflow with low cognitive overhead. Everything is preserved by default (middle click/ctrl click is my default click in a browser), unless I'm clearly in a linear workflow where I don't want to keep the page (left click). Self-organizing due to the way they open, but very easy to manually reorder (or close) if needed. Kept in memory so going back to a (recent) tab is instantaneous.

They just... get out of the way and let me work. Tabs make browsing feel like one continuous task, where history/bookmarks feel like constant interruptions.