Some airlines have gotten rid of intra-Euro J completely. AY hasn't done that but has instead brought back J to some flights it previously declared "one-class". The airlines that still offer an intra-J product are, with the odd exception of SU and TK, I believe, offering a hard product similar to Y with a middle seat blocked on three-seaters. So what you experienced on AY is not different from the competition.

They do move the cabin divider when need be.

The Embraers are terrible planes. A 40-minute hop to ARN works out, but that's about all one can manage. On some but not all Airbus planes, seat pitch in the front of the plane is still bigger than in the back.