It’s easy to treat RSS subscriptions, email newsletters, etc as interchangeable with one’s reading inbox, but they should be clearly separated. (see A reading inbox to capture possibly-useful references)
Inboxes only work if you trust how they’re drained. That is, it’s important that everything added is either read or removed, so that if a reference seems interesting, you can add it to that list with the confidence that you’ll return to it later. One effective way to ensure this property is to add everything yourself.
If you automatically import content, then when you sit down to read, you’ll see lots of content that you have no immediate connection to. That material will be interspersed with content you intentionally added because you had a strong emotional connection, diluting the latter.
If you automatically import content, the reading inbox may intermittently become intimidatingly long. That discourages you from opening it, which makes it less reliable.
If you automatically import content, it becomes more expensive to groom your reading inbox. To decide whether to trash or carefully read those items, you have to first get some sense of what they are. By contrast, if you’ve added an item manually, you usually already have some sense of what it is or have some context which indicates something about its value. It’s momentum-sapping to switch back and forth between evaluating items to be read and actually reading them.
If you add content yourself, you’ll provide your own backpressure: you’ll have some awareness of how large your reading inbox has gotten, and so you might think twice about adding something of dubious value.
The web is full of noise, and so is this fraction of the web I subscribed to. It’s up to me to find some signal . That means I have to decide what I want to have knowledge about, and what is dismissible.