Hi Josh – just wanted to let you know that X confirmed your approach. This is what they said:
The provided instruction is correct since Ethos page titles are part of the landmark templates. And since landmark template isn’t integrated with other post types then yes, it’s the only way. And this one should fix all titles regardless of post types
<?php elseif ( is_page() || is_singular() ) : ?>
Thanks again for your help with this, I appreciate it!