Fb did actually accomplish a huge feat. They connected in a defacto social network pretty much everyone in the world that wanted to be connected via a social network. They had just hit a billion users in 2012, took them 8 years, and the internet existed with a lot of hype and similar pretty much failed attempts of this before they succeeded. I think a lot of people probably forget or are too young now to know what even the early successful internet was like. It had a ton of hype, promise, etc. but just doing something simple like talking to other people was kind of clunky. It was cool because it had all the BBS and forums and niche community stuff. But, I'd venture to say for most people it was a solo experience. You got online, did some reading or research or gamed a bit, but didn't really start talking to other humans online until the late 2000s or later. You definitely didn't have a way be connected with people you actually knew, to your social network as we know it today. Sure, you had email, but we all know that has a very specific purpose and is not exactly social or hitting the same spot. This was actually a world changing product, there was a lot to be optimistic about.

All that said, I am not much of a social media user and never really used Fb much myself. I see the appeal and I see the bad sides of it. I think we'd be much better off without it. I don't necessarily like the way in which it changed the world, but there was a lot to be excited about at this point in time. Not liking the product/company/industry/etc doesn't negated what they achieved.