Exactly. B61-11 and -12 have both shown earth-penetrating capability, which is the main purpose behind laydown. So you can deliver modern weapons from high level and get the hard-target effect desired without the demanding flight profile of a laydown delivery.
SFerrin, I wonder if you're equating "laydown" with any nuke delivered by a bomber. It's not. Laydown is the very particular delivery profile where the bomb lands and then detonates a short time later. It's very fiddly, requires a low-level delivery and specialized weapons, and is useful only for a few specific target types.