The streets were coming from Tiger for the most part.  And Tiger is from the US Government/Census, and that is public domain. However it is not always complete.  And sometimes it's slow because it comes from individual states to get collated to the federal level.  It takes time and it's not automatic.  Sometimes it does get populated and yes if we see someone pointing out that it got added and it's not on the map, this is at least helpful and anyone with an account can update it.

I'm sorry you account got hacked but it's not OSM that got you account hacked - it's typically your computer that got compromised, else my account would have been also hacked. It has not yet as far as I can tell.  In fact you probably can use your google account for authentication using OAUTH2 or something, and then Google can tell that you're adding to OSM after looking at your data...