When you say you want to climb easier, do you mean the current setup doesnt allow you to get up hills comfortably, or do you mean you just want the overall bike to be lighter for easier climbing?
If its a gearing issue, your bike came with 2x11 Ultegra drivetrain which is a road drivetrain that Trek decided to slap onto a gravel bike. Instead of a 50/34 crankset, look into a subcompact one that is 48/31 or 46/30. Instead of an 11-34 cassette, look into an 11-36 cassette. Those changes will give you more gear range and allow you to more easily pedal on steeper climbs.
If its a weight issue, the stock wheelset is supposedly 1600g so there isnt much to drop from that. The drop bar isnt light at 323g and could be swapped for a carbon bar that would save 50-80g. The stem also could be swapped for a Uno7 Lightweight stem that is inexpensive and would save about 70 grams.
Its a relatively light bike in stock setup.