This is an adjusted crosspost from the Hot Start Discord, but I think it's relevant to this thread.
Every wing ever made will flex. A PA28 has wingflex. A Lockheed Starfighter has wingflex. The Challenger has a very stiff wing, and as such you won’t see significant movement in flight. There are no engines out there on the wing, so the bending loads at the root are minimal. Aircraft like the 737 and 747 carry the engines out on the wing, so on the ground the gear supports the engine and the wing will bend down with the engine and fuel weight. In flight, the wing carries the weight of the engine and fuel, and so will flex upwards. The Challenger only carries the fuel in the wing, and it's only just over 2000KG with full tanks, so the difference in flight and on the ground is minimal. Without the engine out there as a mass damper the wing flex is also smaller in magnitude and potentially higher in frequency, essentially it will flex less and stop flexing sooner.
In X-Plane the turbulence simulation feels pretty poor IMHO. Low intensity chop, where the flight path doesn’t change and it feels more like driving slowly over a cobbled or washboard road is most likely to show the wing moving, but X-Plane does a pretty poor job at replicating that - XP11 lacks subtlety in most parts of the weather simulation.
There’s also the fact that real wings show smooth deformation / bending (one single continuous curve) but XP can’t do that sort of smooth body animation, so it’s necessary to chop the wing up into sections and have angles between them. This can then cause other issues with the wing like flap positioning etc. As such, wingflex in XP is a compromise - it will never look perfect.
Goran has been clear that Wingflex is coming to the Challenger, and the devs may have some magic up their sleeves to make the subtle movements happen.
However judging by other addons, large movements of the wing (like a 787 or 737NG) in XP turb are what some sim pilots want to see when they ask for “wingflex”. The Challenger will not have this, as the real thing does not. I think it’s important to set expectations correctly for the community.