This is a great idea!
In the summer break post tenth grade, during which, in India, we have our big exams called the Board Exams, I began a blog where I posted my notes from that year. I still keep it running, and it’s amazing how much readers say it has helped them, which is why I truly appreciate your thoughts on democratizing education.
The kind of blog that you are talking about, however, is a step further, where one should aim to simplify and explain concepts with practical examples. I would love to try it out for those few subjects that I enjoy. I keep waiting to gain in-depth knowledge of the topics, but maybe I will achieve that through blogging about them.