I can see why you would come up with that number. The reality is I tend to watch my movies multiple times. This would give me seven new movies per year. On top of all the other movies already own. Plus I still have cable TV, which there’s a good chance I may shut that down and just go with antenna. Which would still give me all of my local channels.
Right now I buy on Blu-ray, but there’s a good chance I’ll probably start buying on 4K once I get my new TV.