the quality is what actually matters, not really the content

Its not that the content does not matter.

In theory the content does not matter.

But in practice it does.

What really matters is the quality of attention. The content matters so much so that, with some content and with certain times, it is easier to maintain a high quality of attention and approach and attitude and intentionality..

With some other content, its difficult..

Why is it difficult ish to watch some particularly uninteresting content repeatedly?