What part of "Every account you open stays on your credit report for 10 years, even if you close it one day after you open it..." don't you understand?

So every card you have opened over the last 9.999999+ years is still adding to your AoA. My 10 year total of opened accounts is @87, all of which are adding to my AoA, thus my @800 genuine Fico score.

The only way closing an account can hurt your CR is if you only have a few cards, and you carry a balance, which would raise your "utilization" score. But even then, just pay off most/all of your charges before they post, and 'bob's your uncle'...