If clothing is needed in a disaster situation, I don't see how a new retail sweatshirt and jeans would be much more impactful than a used sweatshirt and jeans, given people have enough sense to not donate clothing with non-cosmetic issues - i.e. faded ok; rips/holes not ok).
Furthermore, if you have some money to spend on the effort, buying new cloths is a really poor choice among the options for spending it, for all the reasons they mentioned: organizations on the ground know what items and quantities are needed, often buy in bulk with discounts and, if possible, purchase through businesses local to the disaster, which supports economic recovery.
So the thing is, you need someone to sort donations. Not just for quality but for what they are, so that you can send appropriate things to appropriate disasters. A retail sweatshirt and jeans might be exactly what North Carolina needs, might be barely passable for right now in Los Angeles, and would be less than useless in Los Angeles six months from now. You also have to have someone go through all the donations to figure out what is and is not a non-cosmetic issue and discard the useless because, as someone whose spouse worked for Goodwill, I can tell you that you can not count on people to have sense enough not to donate damaged and useless goods. Then you have to have someone physically get the things from where they were donated, filtered and sorted to the disaster. A whole network of someones, actually, because there are a lot of places a donation can originate. Trucking stuff into a disaster area is a challenge as well, and may be impossible depending on the nature of the disaster in question and where the stuff is coming from. A new sweater is no better than a gently-used but fully functional one if a sweater is what's needed and they're both already on-site. But for a disaster response that's scaled nationally and designed to respond to minor and major disasters of disparate types with varying needs, cash is 100% king.
I don't know. Either things that people say they want are paramount, or not. Unless they are starving, people would say no to "used food" like a hamburger with a bite taken out of it too.
I suppose it depends if you are trying to help with people's wants or needs in a disaster situation. If 10 new sweatshirts and 100 used sweatshirts get airdropped into a disaster area, and all 10 new shirts get taken and 0 used shirts, then FEMA is right, cloths are not needed. However, if the cloths being new help people psychologically cope with the disaster, that's certainly a factor to consider.
Furthermore, if you have some money to spend on the effort, buying new cloths is a really poor choice among the options for spending it, for all the reasons they mentioned: organizations on the ground know what items and quantities are needed, often buy in bulk with discounts and, if possible, purchase through businesses local to the disaster, which supports economic recovery.