While you were gone is different from the algorithmic feed. It's a short section you can easily scroll past to get to the main feed. The algorithmic feed re-sorts the whole thing.
He's talking about the ordering, not the content. Even a carefully curated list of followers will be resulted in a timeline that's destroyed by Twitter's bizarre attempts to drive your attention towards the paid content that's forced on you.
Yeah, unchecking that was the first thing I did after updating the app, and the existence of that option was the only thing that made Twitter tolerable again. But where before I used to read every tweet in my timeline, now I regularly miss tweets because of the 'while you were gone' misfeature (I can tell because I have another device with an older version of the app), which doesn't appear to be optional. Plus everything is out of order.
It's not like I see any more ads this way, so I don't get the point. I do get a lot of stuff that isn't ads but which I didn't subscribe to and don't care about, and it's infuriating. Twitter clearly doesn't want users like me who follow only enough stuff they can actually read. Probably someone's bonus is linked to the average number of accounts followed. It's enough to make me seriously consider not bothering with Twitter any more. I wonder what that would do to their bonus? Facebook already used the same method to successfully drive down my usage of it (and therefore my viewing of ads) by at least an order of magnitude.