I have 16 of these 10-bay HDD towers. They're connected via USB 3.0 over a 16 port USB hub (Acasis) to my computer.
Most of them are filled with either 8TB, 16TB and also 20TB HDD's.

I mostly store TV-series from different streaming services and BD-Rips, movies and documentaries. I also store E-Books and such with "nice to have and know" stuff.
The only thing i don't have that much of is music. It's less than 50TB at this point. But still a well maintained library.