Trust me I tried it! Only the bookmarks became a forest I could not find my way in or out. Atleast when they are tabs, when firefox starts slowing down, i realize there is too much and trim some down.

That said, I use evernote to clip urls that will be useful in the future. The tabs that are open are transient ones, that are required only in the context of a current research or feature implementation and would not be needed once concluded.

I suppose, I am a pathological reader and researcher who needs to look at all opinions, find all apps that provide a feature and try them all, dig deep into each solution etc etc. Sometimes that leads to analysis paralysis. Not at all a good thing.

Bookmarks don't save the per-tab history. With tab sessions you can go back and see what search terms and sites you used to get somewhere.

You can't see the page from the bookmark and you forget the content just from the bookmark title. Well maybe not you but many people including me do.