When the J-160E was originally released in '54, it was X-braced and had a solid top. It was also incredibly feedback-prone, to the point where most people judged it to be unusable. Les Paul proposed changing to ladder bracing and a laminate top as a solution to the feedback problem, and Gibson gave it a try. This didn't exactly make the guitar wildly popular, but at least it was more or less functional and it stayed in the lineup long enough for John and George to order a pair in '62. Which resulted in sales to Peter Asher, Chad Stuart, Jeremy Clyde, and who knows how many others -- but I suspect the number is approximately equal to the number of J-160Es sold since 1962 :) -- right up to the present day.
Think of the solid top as a reissue of the original '54 J-160E, if you like, but with the P-90 replaced by a P-100 to make it functional. The J-160E was a perfectly valid concept that Gibson didn't manage to realize back in the '50s. The Les Paul-ized version was the best they could do.
The bottom line seems to be, Gibson offers reissues of both the original '54 version and an early-'60s version of the J-160E. You can buy whichever you like. What's the problem with that? If you don't want a "'54 reissue", you don't have to buy one.
-- Bob R
P.S. Just a reminder that Gibson used to make a very nice X-braced, solid-topped acoustic with both a P-100 and an undersaddle pickup: the J-190 Super Fusion. A three-way switch allows you play through either or both pickups. Having separate volume and tone controls for the pickups makes the switch as flexible as a variable pot.