I noticed the documentation for adding the apt repo uses the outdated sources.list.d format: https://www.sublimetext.com/docs/linux_repositories.html
Here’s the deb822 format I’ve been using for the repo source definition:
X-Repolib-Name: sublimetext
Types: deb
URIs: https://download.sublimetext.com/
Suites: apt/stable/
Architectures: amd64
Signed-By: /etc/apt/keyrings/sublimetext.asc