I have both hard and soft cases. I have no hesitation to use a soft case with a scoped rifle for routine short transportation by auto or such. My AR's have QD mounted scopes as do many of my bolt guns (usually Talley QD rings and bases on bolt guns). The soft cases protect the scopes adequately.
Even with a hard case, if it is a multiple rifle case, the contents can shift and scopes or rifles could bang into each other with rough handling. A riflescope cover over the entire scope can help. Leupold, Vortex and other companies make them. There are generics as well. They are usually stretch neoprene and protect the entire scope.
I often completely remove QD scopes and carry them separately inside my range bag. I put such scopes inside a sock or put them inside a riflescope cover of the correct size, as mentioned above.
I've not had a scope damaged using any of these methods. I don't think a hard case solves the problem any better, except for long transport where baggage handlers are involved. The example above with the beautiful Sako stock being broken is a good example of what can happen. That is extreme and probably limited to airline baggage handling, but, it illustrates that no system is perfect.
One example of a riflescope cover. Brand name or generic does not really matter as long as it fits. Cheap. Usually about $20 or less.