Just discovered that when you open up the page picker in Obsidian after typing [[ , you can bring up the header picker after selecting the page and typing # instead of pressing Tab or Enter. Saves moving the cursor back to the left of ]] to set the header link.
Actually discovered this after seeing the creator of Obsidian request on Bluesky reports of any papercuts that could easily be fixed. I’ve been making these internal links all day, and was about to propose detecting when the hash key was pressed after selecting something from the page picker. But before posting that, I figured “let’s try pressing hash while the picker is opened.” And sure enough, that worked.