No, preparedness is definitely not a waste of time.
Because every little bit counts. Every bit of knowledge and experience. Your first aid kit is going to help you when you burn at the stove. Your extra stored food might help after you loose your job. Why not prepare in the only way you possibly can, if you are old or sick? You can not be a expert in all the areas of living – being a doctor, mechanic, soldier, gardener ..fisherman
Yes, do prepare in a balanced way – but not for doomsday – Prepare for tomorrow. And with survival experience comes the knowledge of what your family need to be ready for first. If you want to train like a soldier – get fit, learn to fight and shoot. If you do not want to battle with the most basic stuff after everything falls apart – get a water tank and learn to grow vegetables. You may want to buy a hand mill to be able to bake a bread. learn how to sharpen a knife.
You need time to learn all these skills – I would say make a lifestyle out of it …or a hobby at least. You will start saving money soon enough. Simply being able to do things for yourself. Take responsibility for yourself and your family – prepare