(The first, because mine is a nit-picking mind, was to wonder how preference was measured; more time spent reading the feed, presumably, and/or more interaction with it. Maybe how often they “like” things? There are lots of metrics I can think of where the question is basically “does the thing specifically designed to increase this metric do so?”)

The big one, however, is that the algorithmic vs. chronological feed is one of the questions that hinges substantially on what thing or things you are using social media for, and some of those uses are radically different from each other. On your average social media platform you have, at least, people who broadly fit into these categories:

1. Content Creator™. Someone using the social media platform to publish some kind of creative work, who is interested in ensuring that people who are interested in that work can see it. Chronological feeds are key for ensuring that people who've specifically signed up to see your updates can, but algorithmic feeds might introduce you to new followers... if you can convince the algorithms they'll be interested.
2. Entertainment/idle seeker. Someone seeking Content to amuse, edify, or otherwise stimulate them, the equivalent of flipping through TV channels or browsing a bookstore or similar. This is the ideal target for algorithmic recommendations, because this person will often want to encounter new stuff they don't know they like yet.
3. Socializer. Classically, the selling point of your MySpaces and Facebooks was “share what's going on in your life with all your friends and family!” and connecting with people who share your interests, etc. is still a draw for many. I feel like this is the case where chronological feeds are the undisputed winner, because if the point of checking social media is to see what your pal nowhereman32 is doing today, a recommendation of that influencer everyone's watching isn't going to cut it, even if nowhereman32 mostly posts about niche visual novels featuring kinks you absolutely aren't into. Recommendations might help start conversations sometimes, but they're probably not a major draw.
4. Directed seeker. Someone who wants to talk and/or learn about specific topics. Whether an algorithm helps this person depends a lot on how niche the topics are; if there's a lot of options, recommendations can help, but for more obscure topics, most similar/related suggestions will be irrelevant.

Now, all of these are legitimate use cases, and I suspect most of us fall into at least two of these in different contexts, but the central point is that they have fundamentally different needs. What makes a site good to browse for Content may make it less valuable for buiding and maintaining human connections, and vice versa. The directed seeker's case, specifically, ties into what I consider to be wrong with search engines nowadays: ad-funded sites, including search engines, are incentivized to keep you on the page longer, so they now all give you fuzzy matches by default, and this means the directed seeker has a miserable time finding anything with them. But What's Wrong With Search and Why Can't I Find What I Precisely Outlined When I Know it Exists aside, I think we have a more general problem with the fact that a platform that technically supports all of these use cases will have regular culture clash issues when users with different ideas of what the platform is for encounter each other... or when the platform optimizes for one experience at the expense of others.

The broader tension here I think is between discoverability, the ability to find new things/be found by new people, versus user control, the ability to choose what and who you want to give your attention and time. In a lot of ways, this is similar to the tension in software design between making your software easy to use for most people out of the box versus making it customizable for power users, except that it's very likely that all users will want it both ways at least some of the time.

This whole topic ties into both why I haven't written more here yet and why I both love the resurgence of the “homepage” and am reluctant to make one. I'm not a Content Creator, really. I like writing stuff I think is interesting and putting it out there to share with other people, but more from a Socializer angle. By the same token, I like the idea of having a homepage again where I can put stuff that's personally important or interesting about me and share it with people I know/meet, but I don't like the idea of it becoming Content for people to Consume. And there's no having a guestbook or a forum with all the spambots out there.

A thing approaching blog posts as Content might eventually give me is a neat and tidy way to wrap them up. But I don't have one today, so I'll close with the general observation that we need more attention, in the design of the internet at large, on the fact that popular tools will eventually be used for everything they can be used for. It's very easy to make the mistake of assuming that what other people want from their experience is the same as what we ourselves want. And, even for very specific niche tools, that's typically not going to be true.