Twitter is quite frankly worse. And I don't know if I am personally acquainted with even a single person who actively uses LinkedIn. I wonder if the latter is an SV thing?
I don't think LinkedIn use is limited to SV, but the qualifier "actively" makes it unclear what you are trying to say. What is "active" in this context?
A median time between updates of less than 2 months over a 5 year period.
LinkedIn serves the same services as a CV and a job fair.
I've never met a single person in my country who uses either one. Yet everyone I meet has a Facebook account.