I despise LinkedIn with the fire of a thousand suns. The biggest fake, gay, woke piece of shit website I've ever had the displeasure of having to use.
But yes, people need at least 2 of the 3 things you mention.
@UncleIroh yes. you have to know how to use it. by that i mean, avoid reading any feeds or posting anything. it should be strictly for networking/connections and your profile. it's easy to get trapped and start posting content but over time you realize this is purely business and you have to present yourself properly so opinionated posts will most likely make you look bad over time. i had to create a new account because there is no "delete all" functionality. and i stay away from it.
I never used it for posting, that way lies gayness.
Whenever I'm involved in hiring, I do use it to look up candidates and see if they have a posting history.
I used this method to throw some middle-aged leftist feminist bitch's CV straight in the bin at record speed when I saw her arguing in the comments about "muh patriarchy". No fucking way.
@UncleIroh i've also noticed freelancers not having their own website or even github. let alone linkedin. it's like they are all trying to act like some kind of super hackers/spies and must keep low profile. a guy responded to my ad and essentially all he did was under NDA and "trust me bro".