Please add more information to the pull request describing why you want this to be changed.

Updated the information.

For new ROS users I would expect the previous way of setting the parameters to be easier and much less error prone. Each parameter is very simple and separate from the others. Using <rosparam> for this requires writting valid yaml which some users might not be familiar with. So I think this changes raises the bar to understand the example which I don't think it a good idea.

Your comments are reasonable, but in the first look, I thought the <rosparam> does not work for hztest test node. So can I add a comment about the another style of code using rosparam?

Fixed.

Looks good to me. Thanks!.