There's always going to be someone more knowledgeable on a topic than the person teaching others. I think the more fair question to ask is if you are providing value and teaching other people who stumble onto your content.
Absolutely. Expertise definitely helps in explaining a subject, but newbies can also get a lot of value learning from someone who hasn’t forgotten what it’s like to be a beginner.
Exactly. It helps to realize a lot of content you publish is for the stumblers, people who by random chance will come upon your content and it may be the first of its kind that they have seen. New people are always being created.
I'm addition, putting content out there is also a good way to learn from the feedback.