Not sure that I agree with taking away my choice to buy a CDW. I like to know what my exposure is and can I afford it. A deposit can be just that and if the damage is more then you may be liable.
I take responsibility and care when I am out on a boat and touch wood not damaged one yet, but I still get caught out occasionally. Wind, tide , underwater eddies at Stokesby being one in particular. I came in taking what I could into account and still got turned. Rear of the boat nudged the one behind, was meant to be in front. No damage as the fenders were deployed. The boat occupants were very nice and complimented me on my recovery. Other times I have moored there with a foot or two to spare at both ends.
No CDW won't stop the reckless numpties as usually they are not aware of there own inadequacies. It will keep good customers away in my view.
Education has to be the best way forward.