You can absolutely find non-performative posts on Instagram. There is value in a sincere post - ex. sharing pictures of your cat to your friends.
Whereas in LinkedIn no such value exists in my experience - I can't imagine myself posting there for any other reason than to be performative.
So in terms of % of posts being performative I don't think anything tops LinkedIn.
The mighty second brain of course. https://youtu.be/6NukGtwJb7Y?si=yg09jegXRM4C-hFE
I absolutely abhor it the "newsfeed" because it's never once had anything interesting on it, and my inbox resembles what I've heard described from women about using dating apps in terms of how so many recruiters will spam boilerplate messages to anyone with the most tenuous connection to what they're recruiting for, making it a lot of effort to sift through to find anything of substance. I've gotten messages that literally just refer to me having a "background in IT" as evidence that I'd be a good fit for their positions, which is somewhere between "you know how to write code in some programming language" and "you've touched a computer before" in terms of relevancy (and that's not even getting into what I've also heard from women about how men will try to DM them on LinkedIn like it's a social networking app; I have to imagine the experience is even worse for them). It honestly feels like companies have just become overly reliant on it for recruiting nowadays, and it doesn't even end up even working well because too many places can't be bothered to even properly describe the jobs they're hiring for (e.g. tagging them as "fully remote" and then putting in the description that they require 3 days a week in the office), and at least half of the postings aren't even from the companies themselves that are hiring but just from generic recruiting firms that describe a position but don't specify the name of the company. If you can avoid making an account, it's definitely preferable not to, and I envy you, because I wish I had that luxury, but unfortunately I just didn't have any other good prospects for finding a job.
Interestingly, unlike instagram the LinkedIn business model has nothing to do with it. It’s built around b2b sales and professional recruitment.
Then ChatGPT happened and dear lord did LinkedIn ever fall off a cliff. So, so many low-effort, zero-value updates. Far worse than any other social network I use.
A waste of time. Every. Single. Time.
It wasn’t quite as needlessly performative. But it’s never been good.