This steering wheel shake is a problem that is extremely well documented, across multiple users, over multiple sites, who no doubt have taken their vehicles to multiple shops to diagnose and work on across the country. Wheel balance (after balance, after balance, after balance in many cases) has resolved the issue, but the fact remains that 4runners are extremely sensitive to this, at the very least, if not a flaw in the suspension or steering component design somewhere. Your statement that it’s an outright balancing problem is incorrect as there have also been many who have had other things fix it. Is it most likely a balancing problem? Of course.
To be clear, I’m talking about a wheel shimmy on unmodified vehicles. Mine has done this since brand new, and I’ve had 3 sets of tires balanced 4 times across 3 different shops - this is completely ridiculous. You can’t expect someone to put up with that much just to get their wheels balanced.