After closely scrutinizing the new Escale MP vs 2011 DA MP, I have come to some conclusions:
Firstly, The classic MPs have no lining at all.
I’ve seen some posts talking about lining in the classic MP which is why I looked closer and am writing about it now.
The inside of the classic MPs consist of canvas - it's simply the backside of the canvas it’s made of, with fabric sewn over the joined edges. I tried to get good angles so this can be seen. It allows the bag to have slightly more room because it’s just a sewn fabric "bumper" over the raw edges of the outer material. Believe it or not this minimalist approach to the interior lends even the slightest bit more packable storage.
Also, I wouldn't know the precise answer since I'm not in the atelier on the front lines, but maybe they chose to use a thinner mm for this canvas because they know the fabric lining would add bulk. Perhaps they were trying to subtract some chunkiness from the canvas to make up for the addition of that chunkiness gained from the fabric ? Just a thought. Shrugs.
Secondly, the new Escale MPs have a sewn drop-in lining. Which means that underneath that pretty purple cloth lining, there are the same "guts" as can be seen in the classic MPs. The difference is there is extra fabric sewn to fit the interior and then dropped in and sewn around the top for the Escale MP.
So essentially, when I see comments about "cost-effectiveness" and "cheaper" methods with the new Escale MPs, I have to disagree. It is by far more costly to include additional fabric in these special edition MPs. Also, I tried to show in the photos, because of the addition of the drop-in lining, there is an added step to sew all along the interior top of the MP in one continuous length. That means: more sewing = more manual labor = more cost.
In the DA MP, it can be seen in the photo of the interior where the zipper meets the top of the inside canvas, that the zipper has one line of stitching along the top to hold the zipper in place. Thus all of the innards of the bag are raw and out on display. Making it very easy to see how it is constructed. Again, looking at the interior of the Escale MP, everything is hidden beneath the pretty lining and all buttoned up.
Just wanted to point all of this out, if for nothing else but my own amusement. Hehe. I
do not agree in the price increase on the limited edition MP, but it does seem that they are indeed trying to make them "nicer" or have a little bit more of a special interior with some flavor. I agree there is less room due to the addition of the fabric lining, which doesn't bother me personally, but I understand the nuance of it.
I included photos of the zipper issues, mine has it too, sadly. I would venture to guess that this will be the norm for this piece. Very disappointing. The canvas itself does feel thinner and more flimsy. It's like buying poster board (older MP) and then getting one little piece of printer paper (new Escale MP). Lol. The thickness is not at all up to standards as we used to know them.
The zipper issue could be fixed if more attention was paid to where the zipper was being sewn onto the canvas during construction of the piece. It is being sewn too far back. It should be hitting where the older ones hit. I hate to say it but I think the mass production and rushed inventory demands is causing so much to slip through the cracks. More employees hired and trained quickly and less attention paid to detail.

I know I'm not saying anything we don't already know (but is cathartic to type it).
I will be keeping this Escale MP - the pop of color and spring vibe makes me happy. And I probably won't use it enough to get annoyed by the inside bulkiness. But simply having it and being able to look at it cheers me up, so it is what it is. Hope this was helpful in some way to understand at least the construction method of this piece, both new and old.