IMO a camera with manual controls is more important than it being SLR: Manual controls meaning manual exposure settings (aperture and speed), and if possible also manual focus, although the latter is often not present on non-SLRs. Automatic settings have the disadvantage that you rely on the camera knowing what it's doing, which is nonsense really: the camera doesn't "know" a thing.
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One example where you can't fully trust the camera: the camera thinks all the world is mid-gray (a value chosen because it does occur often in nature. Foliage, for instance, is about mid-gray). However there are lots of situations where the light is different, darker or lighter. In those cases the photographer has to override the camerascamera's aperture choice.