Yes! T-pose can be harder to rig and generally makes getting smooth correct shoulder/upper arm deformations, harder. A-pose is just as effective at allowing full control and torso/arm envelope separation, but; without introducing the same problems - (simply, because A it is a more natural / less extreme pose to begin with)…
In my ~30 years of experience rigging (since 3D Studio for DOS), Rigging is ‘done’ a lot faster and requires far less tweaking to get the desired result with A-pose.
-Woody