I wouldn't think any wax/polish would harm the clear coat, especially if the trailer is washed first.
My 2013 has no signs of wear.
I wash with any car wash soap.
I have used Meguiar's Instant Detailer and Turtle Wax with excellent results- slick, smooth, shiny trailer-
2013 Classic 30 Limited
2007 Silver Toyota Tundra Crew Max Limited 5.7 iForce
2006 Vivid Black Harley-Davidson Road King Classic
1999 Black Nissan Pathfinder LE
WBCCI #1811, Region 6, Unit 56