Jumpers. Do I wear them? Yes. Do I think they are frumpy? OK. I wear them around the house as nice looking house wife gear. You usually have to coordinate them, you can nurse in them, they are modest and are comfortable enough to do my daily chores in. They are a step up from sweats and not caring what I look like since I am at home and not going out. For the summer I like making those Elizabeth Lee jumpers out of batik fabric and wearing them with flip flops. But that is not the style, just my style.
Are they what I wear when I want to impress people with my fashion sense? No.
The "frump" thing is also measured by age and personal style. I saw a lady who is like in her early 20's in Church on Saturday. She was in a dark green jumper, a long sleeved off white shirt underneath, and on her feet. Not sandals or stockings, but black polyester bottoms of her calves socks that went up to her these black lace up shoes. She looked frumpy. She actually looked to me that she was literally going for a frumpy look. I mean if you fix the socks and shoes, the outfit would have looked more like nice casual on a much older lady.
Coming form the northeast, I have no memory of jumpers being "in" in the 80's, so maybe it is regional.
Skirts are in right now. You can pop into any H & M or Old Navy and find more skirts, most not short or too short than one can wear. I love this season's fashion.