You can check: <https://github.com/kagisearch/smallweb/blob/main/smallweb.tx...>. I can see that your RSS URL is listed there.
But it currently does not appear in the search results here: <https://kagi.com/smallweb/?search=zahlman>. The reason appears to be this:
"If the blog is included in small web feed list (which means it has content in English, it is informational/educational by nature and it is not trying to sell anything) we check for these two things to show it on the site: • Blog has recent posts (<7 days old) [...]"
(Source: https://github.com/kagisearch/smallweb#criteria-for-posts-to...)
Why would you only include blogs in your small web index? That must be a minute fraction of what is out there?
I can't think of a single blog that I read these days (small or not), yet there are loads of small "old school" sites out there that are still going strong.