Welcome to the forum, Samuel!
“Is it correct to say that Anicca also refers to our inability to stay satisfied with anything in this world for a long time?”
Yes. Anicca has many meanings and that is one; see, “The Incessant Distress (“Pilana”) – Key to Dukkha Sacca” and “Anicca – True Meaning”.
Rest of your comment is correct too!
– Also think about other aspects, like anicca nature leading to one (eventually) getting bad rebirths, and becoming totally helpless (one meaning of anatta): “Anattā – A Systematic Analysis“.