Only if people pay. Which they won't when there's nobody else on there. How do you get your first 100k users?
You might say, well, start with 1000 users. But 1000, or 10,000 isn't enough to make a social network interesting. Maybe you could get around this by making it about a specific niche to start with. But that probably won't work, and if it does, you'll end up stuck in that niche.
On the other hand, I don't think this idea is as impossible as people say it is. It's just highly unlikely to be successful, and far more complicated than simply paying someone on Upwork to make it for you.
