My personal goals are more profile exposure and trying to organically grow my network + steer new eyes to some open source stuff I'm working on w/o spamming a bunch of people.
I used it for a while. I don't know that it increased my exposure but it did let me see who was viewing my profile. I eventually cancelled it after deciding to retire but I could see it being useful to people that want to reach out to more companies.
The "see who viewed your profile", although fulfilling some gossip-like urges is really a pointless feature. Like what would you possibly do with that information?
Anyway, tldr, good source of cold leads.
Edit: re linkedin generally, imo it's really not for posting content with any kind of depth. Anecdotally, I get way more engagement posting shallow stuff there than anything more substantive or technical, so if you're talking about open source, unless you have a great following interested in that or can find a way to make very shallow takes that anyone can understand easily, it might not be the best forum.