I don't think it's exactly apples to apples. The 4R is pretty limited by relatively short front control arms. Kdss version has more articulation than the normal suspension models, but it's still quite a bit less than the kdss lc200. The LC250 should have more travel than the lc200. So, it'll probably be quite a bit more than the 4Runner, even with kdss. Even without a rear sway disconnect. But maybe not as much as the gx550. Maybe more? Hard to know until we get our hands on them.
The LC should be a lot more buildable too. It has the equivalent of a +1.5 per side long travel on the 4R, much better gear spread on the transmission, a bigger 9.5 rear axle and 8.7(?) front diff. And it appears to fit big tires a lot easier. 35s are really challenging on a 4runner. 37s are super easy on a tundra. Hopefully it'll be like the Tundra. In my ideal world the front suspension is interchangeable with Tundra and it'll be really easy to get to 13-14" of travel and 35-37 tires.
Out of the box, it's maybe similar. But I think it will be a lot easier to build a decent trail rig.
Of course that is vs the current 4runner. The new Tacoma has everything the LC has along with better shocks and OEM off-road stuff like factory jack points in the bumper for high lift jacks. If history holds, the 4runner gets all that too. In that case it's probably the better off road model. But arguably it has been for a while. There's a lot of different types of things that make up off-road - but more technical terrain favored the old 4R in a few ways. And the LC moving to the old 4runner space opens the 4r to go a bit more enthusiast on the spectrum. Maybe it'll come with 35s factory or something more competitive with Wrangler and bronco.