No, changing the name of the directory via some sort of file manager is the only way to effectively reset the theme, besides just deleting it of course.
It looks like you're not alone though https://wordpress.org/support/topic/alexis-broken-in-wordpress-46 so it's probably time to consider a newer theme. The Twenty Sixteen theme is our current default, so that will give you something basic and stable for now, and there are lots more to choose from: https://wordpress.org/themes/browse/new/