What brought me around was the Easel feature for scrapbooking pieces of multiple web pages onto a single page. For some kinds of research, being able to see everything at once beats anything I've been able to do with multiple tabs or window arrangements. I used to arrange screenshots onto a photo editor's canvas, but doing it in-browser is an easier workflow, and Arc makes it easy to get back from the clipping to the source.
I believe that Beam is similar to this feature, except (pro) better support for daily notes, and (pro and/or con) clippings are in a list instead of arranged in 2D.
That fact that these blocks can optionally be live also makes it useful for constructing ad-hoc dashboards.
[1] "Arc | Collect Your Internet with Easel" https://youtu.be/ukquBSOpmTk