Yes, you are now stuck with the bald areas for an indefinite time. The dead leaves will drop out but the bare stems cannot be expected to re-sprout. The only way most conifers so pruned re-cover any such sections to a significant degree is by branch-lets from adjacent foliage areas growing across the pruned sections from the sides or bending down over them from above. As this is an upright growing type very little of this may happen in this instance, the new growth all being directed away from the newly exposed basal areas.

"The only way most conifers so pruned re-cover any such sections to a significant degree is by branch-lets from adjacent foliage areas growing across the pruned sections "

That's highly possible, as prior to me doing this, they haven't been trimmed in decades, and have grown quite shaggy.

a before shot.