What of ROS2 is ROS_DEBUG of ROS1 equivalent to?

ROS_DEBUG of ROS1 is equivalent to What of ROS2?

The equivalent is RCLCPP_DEBUG(logger, ...) where logger might come from your Node, like node->get_logger(), see:

http://docs.ros2.org/ardent/api/rclcpp/logging_8hpp.html#a44818c8a1fd292cd0e81759e956765d7

Also this might be of interest:

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