But window curtain can “soften” the look of any room and make it feel cozier. The right curtains can also make any room more attractive, but they also have a functional as well as aesthetic appeal. By closing the window curtain, you can ensure privacy for you and your family an according to the thickness of the window curtain fabric, you can filter or block sunlight. The sun’s ultraviolet rays can damage carpets, rugs, and upholstery, so by partially or completely blocking the UV light, you can protect your belongings, and of course, subduing sunlight can also help keep your home cooler in the summer months. If you choose a window curtain with insulating properties, you can also help keep your home warmer in the winter
I agree with the heating and cooling properties but blinds function in these areas just as well.
As for privacy the house has no immediate neighbours so that is not important. Nor do I have immediate neighbours where I am now either. The only blinds that get closed here occasionally are the ones on the western side where the sun comes in.
I'm just preferring the more sleek and uncluttered look these days. Becoming a bit 'minimalist' in my old age maybe?