My opinion is for a freshly built wheel the spokes should fill the nipple.
with proper spoke calc not a problem.
In days gone by not a problem as spokes were available in one mm increments.

aside from a rim where the protruding spoke will rely on the rim strip or base tape to immediately protect the tire…too long is no good at all .

try to achieve that fill to the slot.

that written, I have a few bikes where the original spokes were what I think way too short.
the nipple itself was taking the entire tension.
they had held up, but sub par spoke length use.

for aluminum nipples… always should be filled.
Period.