I believe this facebook coin will fail. Only boomers uses facebook these days and they dont have a clue how cryptocurrencies work. They will treat it as some generic digital coin, like those you use inside MMOs for example. It will be restricted to facebook, which is a dying platform, practically an icon of nocoinery and technological backwardness.
I don't think it will be restricted to facebook, that's why it's so dangerous...

https://www.theblockcrypto.com/2019/06/14/facebooks-cryptocurrency-partners-revealed-we-obtained-the-entire-list-of-inaugural-backers/