Okay, another:
Focus on community. Foster online community.
Create easily searchable references on the web. Not just documentation, but also forums and wikis. Make it so when somebody pastes an error message, they can immediately find a page where people are working through sorting that issue. Don't make them join your stupid Discord (you can't search the web for Discord messages!!)
Actively encourage users to ask simple, easy questions, simply as a way of getting them used to asking questions. Ban the phrase RTFM ("Read the friendly manual", except we all know the F secretly doesn't actually stand for "friendly"). Don't dismiss users who "didn't do enough research before asking" -- many of them may not have known what to look up because they're so new to all of this. It's easy to be blinded by your own competence that you forget what it's like to be a newbie. That's not to mention how dreadful online search has become nowadays.
I also suppose it goes without saying that you need to police and moderate your communities, and be explicitly welcoming to marginalized communities by being anti-racist, anti-transphobic, etc. This needs to be the No Bigots Club.