As someone who often carries a lot of tabs, I often keep the tabs around because the cost of evaluating whether a tab is worthwhile or not is high. It usually pulls me out of flow and pulls me into whatever article is bookmarked, which slows me way down.

It'd be nice to have them slowly fade away so I didn't have to make a decision because most of the time, I don't need the tab and wouldn't even remember that it's gone lol.