From a Physics standpoint that is certainly true, but we have human nature involved here. In California, motorcycle lane splitting is allowed only with a low differential of speed (15 MPH). You split 15 MPH traffic at 35, you can get tagged under the speed limit, and likely get dead from being too clever by half.
Many states do not allow lane splitting at all, because of the wiggle room it gives bikers on differential of speed, at lower road speeds.
Again, I’m not for lowering speed limits...I’m actually for raising them in my state of Wisconsin. The speed limit should be set at whatever a reasonable degree of safety can be expected. If they can create roads and cars engineered that people could drive 100 mph on the highways without undue traffic accidents/fatalities, that’s fine with me.