Retroactive Pipedream... if only AC refurbed 333 as 1 x 1 x 1. Again, retroactive pipedream. Probably other logistical issues I didn't raise or think of. But again, wishful thinking.
Replace aft J with PY and now they need more J seats to cram in.
It's 333 DC J still better than the gawdawful 1st gen 777HD J cabins (remember those?)... but yeah the 333 refurb J is probably the only mainline widebody J seat that I would prefer in its XM version.