Giants will clone and make a piece of shit. Apps like this survive by creating a network of people. They do that by creating demand to join the service. How do you do that? Make it invite only, and invite a ton of high profile people and get them using and talking about it, creating FOMO.
The only people who threaten this are Facebook and Twitter. Twitter _actually_ could clone it or buy a competitor. But, look at Twitter’s history of that. They literally KILLED a TikTok by buying it and shutting it down. They are in the process of killing a live video competitor to twitch and youtube called periscope.
Don’t be afraid of The Big Bois.