It's true that it's harder to stay present on addictively designed feeds. But I find it difficult to stay present even visiting traditional websites / classic style forums. We also constantly get distracted reading books. Our minds are estimated to be wandering between 30 and 50% of the time during pretty much any task, even without phones or social media [1].
Presence and intention are skills–they can be trained. Don't expect significant benefits if you switch out addictive internet for classic without also training your attention. This applies for anything of this nature. A few weeks ago I took a weekend without any devices as well as a lot of awareness practicing just during everyday tasks, and one interesting benefit was how it allowed me to take enjoyment from mundane tasks–I stopped thinking of them as things to get done as soon as possible to get back to the computer and started just being.
If you meditate just a few minutes each day, you will start actually noticing yourself getting distracted and then shift to awareness. It feels annoying that you got distracted, but that just means it's working.
The reason to do this is we are much happier when we are present–a wandering mind is an unhappy mind.
I highly recommend Born to Flourish [2] for an introduction to meditation and the science behind it (it's still easy to read).
[1] https://neurosciencenews.com/mind-wandering-focus-25745/
[2] https://annas-archive.gd/md5/0e405c329f33fcb63b4647e386f0ad7...