Remove datePublished and dateModified properties from the Article schema for Posts

add_filter( 'aioseo_schema_output', 'aioseo_filter_schema_output' );

function aioseo_filter_schema_output( $schema ) {

	foreach ( $schema as $index => $graphData ) {

		if ( empty( $graphData['@type'] ) ) {

			continue;

		}

		$type = strtolower( $graphData['@type'] );

		switch ( $type ) {

			case 'article':

			case 'blogposting':

			case 'newsarticle':

				unset( $schema[ $index ]['datePublished'] );

				unset( $schema[ $index ]['dateModified'] );

				break;

			default:

				break;

		}

	}

	return $schema;

}