Wordpress - Remove "Category:", "Tag:", "Author:" from the_archive_title

You can extend the get_the_archive_title filter which I've mentioned in this answer

    add_filter( 'get_the_archive_title', function ($title) {    
        if ( is_category() ) {    
                $title = single_cat_title( '', false );    
            } elseif ( is_tag() ) {    
                $title = single_tag_title( '', false );    
            } elseif ( is_author() ) {    
                $title = '<span class="vcard">' . get_the_author() . '</span>' ;    
            } elseif ( is_tax() ) { //for custom post types
                $title = sprintf( __( '%1$s' ), single_term_title( '', false ) );
            } elseif (is_post_type_archive()) {
                $title = post_type_archive_title( '', false );
            }
        return $title;    
    });

Use function single_term_title()


For CPT title Without word: ‘Archive’:

If you are building custom archive template for a CPT, and want to output just the title of the CPT with no extra word like “Archive” use following function instead:

post_type_archive_title();

From developer.wordpress.org