For me at least, it's basically a substitute for a good bookmarking system. I want to get back to that tab eventually, but if I just bookmark it, it'll get lost in the churn and forgotten forever. I hope some day there will be a holy grail of bookmarking software which somehow solves this, but I don't even know what that would look like.

If I'm working on a specific project and find a great resource, I'll definitely paste the link in an Obsidian note and close the tab. But there's plenty of stuff which doesn't quite fit that workflow.