git rm --cached <file> Blu-ray (1×) ~36 Mbit/s
MS-Glass (single beam) ~25.6 Mbit/s
MS-Glass (multi-beam) ~65.9 Mbit/s
That's ~7-18 days per 120mm x 120mm medium (4.8TB).
Glass prices stable for now. Also, the authors make no statement about horizontal vs. vertical storage.
Somewhat related: 'Your car’s tire sensors could be used to track you': https://networks.imdea.org/your-cars-tire-sensors-could-be-u...