The exact opposite is true.
Take a 4 wheeled vehicle. In most cases, you could dig a hole under one wheel untill it was dangling, and the vehicle would happily sit on the three remaining wheels, albeit with the whole vehicle , and especially that corner lower. The weight normally supported by the wheel in the hole is transferred to the other three wheels.
That is to a large extent what happens when one wheel of a four wheeler crosses a pot hole, and similar load transfer takes place TO a wheel going over a bump.
If you tried the same hole digging experiement with a three wheeler, the wheel would just keep dropping and dropping to the floor of the hole until the entire vehicle fell into the hole.
This is why three wheelers FEEL rather unstable. The entire vehicle rocks this way and that to keep the three wheels planted on the varying terrain. In a four wheeler, the suspension transfers most of the static load to the diagonally opposite wheel. In a three wheeler, there is no such transfer possible. …without a diagonally opposite wheel to react against, the suspension has only the inertial load (both linear and rotational) to act against. The suspension can only react for dynamic loads occuring above the resonant frequency of the suspension.