these look interesting for hosting density in a few years https://www.anandtech.com/print/14711/toshiba-introduces-new-tiny-nvme-ssd-form-factor Toshiba Introduces New Tiny NVMe SSD Form Factor

very cool

of course Google can't use it, too small

can't use anything someone could smuggle out of a DC

for datacenters the ruler format makes more sense

hard to smuggle a ruler

but for that could be interesting for all sorts of ghetto rigging

there might be multiple reasons why they are full rack depth long and 1U tall, indeed