I third this. I ended up crashing my car once because I lost control on the highway after a bump. All I knew is one second I was driving straight and the next second my back end was going sideways. My shocks were completely dead and the bolts were so rusted on the mechanics took two hours getting them loose. Replace them.
I imagine it has a knock on effect on wear and tear of other components, like CV joints, wheel bearings and various bushings.
People always forget to provide the basic information of what type, model, year, of the vehicle. Details like that matter. Some cars can be done simply and cheaply, some are going to cost you more. So some times $1200 would be reasonable to have a shop do it, and other times $3000 would be reasonable.
Believe it or not, the suspension of a 2000 Camaro is different from a new BMW.
Having said that, yes you do need to repair this if you are going to keep driving the vehicle and expect that you and your passengers will be safe. As noted above, the suspension isn’t just for a smooth ride, it keeps the tires in contact with the road. Your steering and brakes depend upon this.