JFem, I just went to the Bnos melachim presentation and Rabbi Forcheimer of Lakewood spoke about these shirts. He didn’t say the shirts, or even the sleeves are problematic but focused on how if the top layer isn’t loose then the body shaping is a problem, so baruch shekivant 😉
Re Feif Un: the rav also referred to the gemara (I think) that mentions the obligation to cover the shok. He didn’t speak about elbows but did talk about the need to cover the entire kneecap, and the advisability (actually, he calls it a halachic obligation) to wear skirts longer than that while standing.
Mandy, I agree. That doesn’t mean that we shouldn’t address the other issues.
And on the way home I was talking to my kids, saying how grateful I am because they could so easily become fashion victims like this kid down the street (not Jewish) who went wild in her tweens. I didn’t want to talk about specific people but mentioned a neighbor who doesn’t cover her hair yet is very tzniusdik – she is so unpretentious and simple. I was so proud of my kids for “getting it”, and understanding how much tznius is also an attitude, and how they don’t need to look down on others who don’t follow what has become normative (hair, knees, elbows, collarbone).