File this post under, "Thinking out-loud with no real answer unless you're a design engineer at Trek."
Having owned a 2020 Trek Domane SL7 for the past two years, it's my experience that the Domane is an excellent endurance bike that aids in helping me feel less beat-up after each ride, which is what an endurance bike is supposed to do. In addition to really wide 700x32C road tires which obviously absorb a lot of shock, it also has front and rear ISO decouplers.
I've noticed that in Trek's latest line-up of bikes, only the Domane still has the
front ISO decoupler system which seems odd. I would've thought that the latest Checkpoint would've had it as well and perhaps been an option on some of the Boone frames (although the Boone is a weight-weenie's CX bike, so maybe not.) I'm starting to wonder if the next Domane frame refresh will drop the front ISO decoupler as well. Perhaps the added weight, cost, and complexity of the front ISO decoupler doesn't offset the gains it provides and hence it not being adopted on other bikes in Trek's lineup?
Since I now own only my Domane, I can't comparison test another bike w/o the ISO decoupler but with 700x32C tires to see if the ISO decoupler is significantly contributing to reducing shock to my hands and wrists... or if it's the wide tires doing most of the work. Do any of you own a Domane w/ front and rear ISO decouplers and another bike with 700x32C tires but no ISO decouplers to compare? Is the front ISO decoupler worth it to you or should it head for extinction?