Initially, LinkedIn was just another site where you could find jobs. It was simple to use, simple to connect with others; it even had some friendly groups with meaningful discussions.
And then it gained monopoly as the "sole" professional network where you could actually land a job. If you are not on LinkedIn now, you are quite invisible in the job market. Recruiters are concentrated there, even if they have to pay extremely high prices for premium accounts. The site is horrible now: a social network in disguise, toxic and boring influencers, and a lot of noise and bloated interface to explore.
When Google decided to close their code.google.com, GitHub filled a void. It was a simple site powered by git (not by svn or CVS), and most of the major open-source projects migrated there. The interface was simple, and everything was perfect. And then something changed.
GitHub UI started to bloat, all kinds of "features" nobody asked for were implemented, and then the site became a SaaS. Now Microsoft hosts the bulk of open-source projects the world has to offer. GitHub has become a monopoly. If you don't keep your code there, chances are people won't notice your side projects. This bothers me.
Rant over. I hate internet monopolies.
I was pressured into creating a profile in Linkedin and publish whatever shitty codes I could get on just so I could apply for interviews (which never got past round one). It's funny, because I got my first (and current) job in programming through connections made well before getting into IT.
My github profile is sitting there. Linkedin also sends me regular spams about how $user I never heard of posted some stuff I won't be interested in. Sure, I could actually use my Github as repository for coding outside work hours, it has its uses. But Linkedin? The place where cocksuckers gather to suck even more cocks from suits?