Surely not so?
We had a pram and then a pushchair for DD which faced the pusher, and turned her round when she was about 2, and then she would usually tell us which way she wanted the pushchair...
But we got a sling when she was a colicy, sad 4 month old, and she howled when facing in, but was happy and content facing out!
Doesn't it depend on the child?
(ok, so I am listening to Jeremy Vine - so shoot me!
)