"Yuck" (sometimes spelled "yech" but still pronounced as "yuck") is not necessarily out of fashion....many people will still involuntarily utter it when faced with something distasteful. "Yuck" is used more as an actual exclamation rather than as an adjective for something disgusting.
"Ick", on the other hand, is not as readily exclaimed but is used as a common adjective to describe something unappealing. For example, if I told you this particular YouTube video showed a human autopsy, you might decline to view it, stating "That's too icky for me." However, if you were to watch the autopsy video with no warning of what you were about to see, you would most likely wince, avert your eyes and make a "yuck!" or "eeew!" sound, not "ick."