With the tech we're talking about, there are definitely limits per inch. They'll be able to fit a petabyte in a 2.5" SSD drive case before the SSD sunsets, at a cost of $300. At that time, your 100tb SSD might be $50 to $75.

After SSD, what technology will take us to 100pb drives at $300? Is that even possible, while keeping the small size of the drive? No idea. It's going to require some amazing breakthroughs.