There are millions of users of FB alone. There's no denying the fact that in some way, this will really aid in spreading the concept of crypto in our everyday life. If some people don't know how to deal with bitcoin and other altcoins, maybe this is the time that they will appreciate the existence of altcoins.
They claim they have 2.5+ billion users? Just wondering how many of these are fake.
However, it will help cryptocurrency to go mainstream easily since people will have idea about it.