I worked for a social media management app company (Sprinklr/Hootsuite/Sprout-esque) and we had the exact same problem. My ballpark estimate is that at least 90% of the messages that went through our system were extremely obvious spam or scams. However, there was a huge focus on MAU growth, so there was no way in hell we were going to attempt to combat this.
For legacy implementation reasons, the backend service that published messages to Twitter would lose 1-2 queued messages every time the service was redeployed. Bleakly, the engineering team decided to not consider this a major issue, despite it being a core competency of the platform. It was simply extremely unlikely anything of value was being lost.