There are many here on the forum who are in their fifties, sixties and beyond. I look around in the real world and see a fair number of genetic women in our age group who dress age appropriately, but are not particularly "feminine" or stylish. Those who are more feminine and stylish often wear things that would often/usually be worn by younger women. Age appropriateness as a test of style seems no more legitimate than 'gender' appropriateness for a crossdresser.
The things I tend to choose for myself are generally simple and less dramatic than what others might wear. But, many of the things that catch my eye are from the juniors department. I'm not trying to impress or attract others so appropriateness is not something I concern myself with other than to suit my wife's comfort level.