I think that it reassures the more nervous fliers. If the pilot is talking about altitude and weather rather than possible engine problems*, such folks will be more relaxed (and therefore cause fewer problems). The calm tone of voice is important.
The stuff that goes through nervous fliers minds can be incredible. So anything that implies “We’re not going to crash and burn.” may be soothing.
I find it a nice reminder that commercial air travel is not teleportation where you magically disembody at your point of departure and re-materialise at your destination, even if it may feel a little like it - you’re still traversing the points in between. An aspect which I have thought about in another thread.