Automatics had shift positions for lower gears for engine braking when going down steep hills long before the manual gates were common. It might be a convenient design that allows them to accomplish the goal in a slightly smaller package, but it's certainly not required for that functionality.
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The whole point of these is to be able to do engine braking to save up on brake pads, contamination and avoid brake fade.
Automatics had shift positions for lower gears for engine braking when going down steep hills long before the manual gates were common. It might be a convenient design that allows them to accomplish the goal in a slightly smaller package, but it's certainly not required for that functionality.
Sure it is packaging it in a nicer way but switching to manual is really the only decent reason to do that.