The lights in a diagonal shaft (in which the turbolift cabin is of course keeping a vertical position!)
But that would mean both that the lights would go past the windows diagonally in the general case, and
that the shaft would have to be wider than the turbolift is. The first would be contrary to evidence (or indicate complex rotations for no obvious purpose other than hide the angle of the lights passing), the second would simply be inconvenient. We know that tiny spaces such as shuttlecraft can easily be provided with gravity independent of outside gravity or accelerations; tilting the turbolift would be a possible solution, then, and it would definitely be a sensible solution."
No, it would not
mean that the lights would go past the windows diagonally.
Print out a sheet with parallel, thick and wide horizontal lines (that correspond to / are in allignment with the deck levels). Take a smaller sheet, fold it and cut the "turbolift" window out. Place the "turbolift cabin" in the bottom left and start moving it diagonally over your sheet with the lines (turboshaft lights) to the top right. All you'd see from the cabin's inside are turboshaft lights that (seem to) go down vertically.
Especially in the connecting neck section a bigger turboshaft could make sense to accomodate freight cars, taking materials from the storage holds at the bottom of the engineering hull up to the saucer section. That doesn't imply that all turboshafts are as big as the one running diagonally through the "neck".
I think it would rather have the function of a "spine" from which smaller turboshafts for passenger cabins spring like the "ribs" in our bodies.