IMO out dated.

Sheers can be used to add depth to drapes or a softer feel.

There still used when the design calls for them. If you need slight privacy sheers can help. If you want formal or girly girly sheers are there. There are now new materials where you will see metallic sheers in modern rooms.

I don't think they are dated. There are many modern spaces that have sheers. It depends on the material and model as well.