What engagement means is that your articles are read. It does not mean that you talk to or support other writers.

I 'won' all four $500 bonuses and I got an 'audio' bonus as well.

When the publishing industry talks about reader engagement, they mean that the readers like to read your stories.

In other words, these bonuses were paid to hte people who earned the most, because they were the most reaed. It has nothing to do with 'supporting other writers.

If one wants to improve one's stats, then one writes well enough for people to want to read one. This involves being a good writer and writing about things that catch people's attentions. Writing for other writers means that one is not writing for readers. They are very different things. A reader is not interested in becoming a writer.