I have been writing this zettelkasten now for about 3 months. It has absolutely been growing crazily. Sometimes I write several posts in a single day. When I am writing my posts, I interlink them with whatever relevant posts and I have already written. In that way, my zettelkasten grows. If you truly want to accelerate your thinking and grow you understanding more, you must proactively spend time reviewing, reading, and relinking (3Rs) your older posts. Try to spend some time once a week, once a month, or once a quarter reading through your old posts to refresh your mind. Review the content to see if its still accurate. Does it need to be updated? Do you have new learnings that you should add to it? Should you split up the post into smaller atomic units? Do they need new tags? Then make sure you add new links between to your posts so you can grow everything. I aim to have at least 2 links to other posts for each of my posts. If I have posts without any links, then I consider that a problem and must fix it. If you do this, you can amplify your thoughts and your zettelkasten will continue to grow.