yeah you can just copy the meat of the xacro into your urdf...its all the stuff in the <xacro:macro>
section. alternatively, you can add a <xacro:create>
tag at the end of the realsense file and then just <include>
it in your urdf.
but you should really get comfortable with xacro. its great.
i feel your pain I had learn the xacro format while adding a _d415.urdf.xacro file too. but no. you don't need to make everything a macro and call it in a common file.
here is an example of making a common file to call all the macros I made
<?xml version="1.0"?>
<robot name="arlobot" xmlns:xacro="http://ros.org/wiki/xacro">
<!-- A common file to tie together all of the bits and bobs of the entire robot
Modeled after turtlebot_description
NOTE: All Gazebo references are gone, so simulation will have to be rebuilt if you want it -->
<!-- From $(find turtlebot_description)/urdf/common_properties.urdf.xacro -->
<!-- It is required by asus_xtion_pro.urdf.xacro -->
<xacro:property name="M_PI" value="3.1415926535897931"/>
<!-- Include 3D camera -->
<xacro:include filename="$(find realsense2_description)/urdf/_d415.urdf.xacro"/>
<!-- Arlo -->
<xacro:include filename="$(find arlo-description)/urdf/arlo_temp.urdf.xacro"/>
<!-- RPLIDAR -->
<!-- <xacro:include filename="$(find arlobot_ros)/urdf/asus_xtion_pro_chrisl8.urdf.xacro"/> -->
<xacro:arlobot/>
<xacro:stack_circles parent="base_link"/>
<xacro:sensor_d415 parent="plate_0_link" use_nominal_extrinsics="true" add_plug="false" use_mesh="true">
<origin xyz=".1945 0 .00475" rpy="0 0 0"/>
</xacro:sensor_d415>
</robot>