The phrase "to cushion the impact" means to reduce or lessen the negative effects or consequences of something. It's like adding padding or a soft material to absorb the force of a hit, making it less severe. Full definition
The luxury car ends up on top of the pile of cars and the deep upholstery cushions the impact. (religion-online.org)
Maintaining a strong social network may foster good health in part because support from sympathetic friends and family helps cushion the impact of life's blows. (discovermagazine.com)
New C3's seats provide generous width, lumbar support and comfort to help cushion the impact of uneven road surfaces. (motor1.com)