meirG, sorry for imprecision, my math mind does not distinguish between A = B and B = A. As your quotes point out, there is a difference between trying to have inside to outside and other way around.
I understand the merit of the idea of keeping outside appropriate and then inside will follow. Still, you need to be careful with that. When everyone focuses on the outside as a routine, then there is less impetus to work on the inside and you are throwing overboard those (the best) who focus on inside. This would affect shiduchim, yeshivos (“which one is hardest”). This makes Satmarer’s quip a little troubling, hard to judge out of context, I presume it was humorous, maybe based on his prejudice.
I am may be misremembering, I think in Slobodka they dressed casually, and Novordok innovated dressing up yeshiva boys as if they were talmidei chachamim already, a forerunner of modern “positive”, self-esteem improving education.