In WordPress 5.5 the deafult comment_type isn't an empty string anymore, it is comment.

See: https://make.wordpress.org/core/2020/07/29/miscellaneous-developer-focused-changes-in-wordpress-5-5/

The problem is in this line:
https://github.com/elmastudio/yoko/blob/master/functions.php#L258

It needs to be case 'comment' : for WordPress 5.5.

I am not sure if this repo is still maintained. Because of the long standing issues here. Would you be interested in a Pull Request? After elmastudio/aino-theme#66 I am not sure if PRs are something you are looking for ...