I am adding this on behalf of audunmb from the review they shared on WP.og forums.

The main drawback of FSE is the missing responsive design options depending on the screen size. For example having different design options for mobile, tablet, or desktop mode like with other editors.

Additionally, it is a bit confusing or hard to realize how one can add the site icon. With FSE you have to change the settings for the Logo block to also display the same image as the site icon. Can you make this option a bit more visible than it currently is?

WP.org review