Taproot supports the block editor first and foremost, and provides its own styles for core blocks both in the editor and on the front end. While content added via the “classic” editor should still display with theme styles, certain features do not have backwards compatibility. For example, it is not possible to access the post level theme settings such as layout, hero image and post title outside of the gutenberg interface.
If you wish to enable these features but still use the “classic” editor, you might take the following approach. Temporarily disable “classic” mode, and set the desired settings in the Taproot Page Settings panel. After saving, re-enable the “classic” editor and add content as needed.