It is, but it's a bit confusing. There's a couple of different things at play here:
First, mastodon.rxbrad.com reports it is running mastodon+glitch. So I expect you're using its feature that lets you write Markdown when you post.
Your server then converts that Markdown to HTML and sends the HTML on to the rest of the network. So Pachli doesn't see the backtick characters you used, it sees <pre> and <code> elements.
I.e., you're writing something like this:
This is some `code`.
