I think a huge side effect of the focus on being welcoming is that it attracts a lot of juniors. The more beginner-focused stuff also tends to bubble to the top out of popularity, but over time I really hope we can improve the algorithms to be the right relevant mix of content for everyone.
Almost by definition, these things take time. We can't rush it, but I think the platform will eventually host the kinds of deeper, more advanced articles and discussions a lot of folks are looking for.
It will happen as we improve platform mechanics to serve different user groups effectively, but as you mentioned, it should also happen naturally as folks grow up on DEV.
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