rest_pre_dispatch conflicts

This function is hooked into rest_pre_dispatch: https://github.com/AdvancedCustomFields/acf/blob/fd6fbd054972ea4d54d3edc92fe66cf2b713d0ec/includes/rest-api/class-acf-rest-api.php#L26-L44
This method basically void method ( in the end it will always returns null )

the filter priority is 10 ( which is default, and higher chance to possibly conflict with other plugins that utilize this filter )

add_filter( 'rest_pre_dispatch', array( $this, 'initialize' ), 10, 3 );

meanwhile the core filter expects a "possible" return value:

/**
	* Filters the pre-calculated result of a REST API dispatch request.
	*
	* Allow hijacking the request before dispatching by returning a non-empty. The returned value
	* will be used to serve the request instead.
	*
	* @since 4.4.0
	*
	* @param mixed           $result  Response to replace the requested version with. Can be anything
	*                                 a normal endpoint can return, or null to not hijack the request.
	* @param WP_REST_Server  $server  Server instance.
	* @param WP_REST_Request $request Request used to generate the response.
*/
$result = apply_filters( 'rest_pre_dispatch', null, $this, $request );

Sample Case:

• Plugin A utilize rest_pre_dispatch priority 10 and returns WP_Error
• ACF trigger initialize method, since this method basically always returns null, the previous filter WP_Error would be useless
• That makes plugin A broken, and it should not Plugin A responsibility to make it work with ACF.
• It is ACF issue that always override $response to null

Start in includes/rest-api/class-acf-rest-api.php at the rest_pre_dispatch hook and initialize method, then compare its behavior with WordPress's rest_pre_dispatch contract shown in the issue. Trace how prior filter results are passed through and identify the existing REST API tests covering dispatch responses. Done means another plugin's non-null response, including WP_Error, is not discarded by ACF.