Why don't you try repeating this silly analogy by giving the 98 pound
weakling a full set of pads and regulation football gear and strip
the linebacker naked. The weakling will still only weigh around 120
pounds but will be able to walk away from the collision, unlike the
linebacker. Or to stretch the silly analogy games even further, why
not ask yourself how it is that cops can walk around wearing nothing
but a thin vest of composites and polymers and still live after being
shot with a piece of lead moving fast enough to have KE that makes
your linebacker look like a lightweight? Kenetic energy is important
when trying to figure out who will survive a collision, but you are
better off betting your life on smart designers and materials
engineers than high-school physics.
jim