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Another benefit would be the same UX for all text content consumption.

If that's how we're looking at it, wouldn't that be the same essential idea as leaving a bookmark and juggling a few books at once?

Of course, but if you are lost in a good book, you don't notice when one chapter ends and another beings. You are lost for hours, and don't think about changing to some other article or paper.

Sure. And with the Netflix model you can binge on episode after episode. There are a lot of similarities.