Yes. I don't understand why you find this concept so difficult to grasp.
If all the pieces ever produced were remade you could buy them from DS and assemble any set you want, but it would cost several times the original set price. Boxes are NOT remade for the DS market so any set in a box must be at least partially original.
Not all pieces are still available from DS, but many are, even pieces originally released years ago.
Some pieces are so popular through DS that Playmobil appear to still be making them for that market alone. However it could just be that they made a lot of spares years ago, and they will eventually run out.
Even recent pieces (e.g. roman helmet 30 26 5810) run out at times but more are made, so it is possible to order, be told it isn't in stock, and then a few weeks/months later it is back in stock.
This is particularly noticeable for the US market.