I know of someone who lived like that, my stepdad's aunt. After her "partner" died, apparently she just kept everything that wasn't trash. My parents went to clean her house out after she died, there is a picture of a man who stands about 6' tall next to the window, he is right at the window, and the clutter was up to his chest.
It was almost nothing but paper as well. There were newspapers from the mid 80s in her apartment, she just saved all her mail, all her newspapers, everything.