Used to develop readers based on similar UHF chips (868 MHz in EU). They were quite expensive compared to printed bar codes those were replacing. Also large. With (folded) antennas we are still talking about 40*10 mm minimum for the label. You can not use them on metal surfaces. Readers nearby will interfere as it works by EM wave backscattering, unlike NFC which is essentially a transformer (with electric field intentionally supressed usually). I think it still is a solution looking for problem. QR codes are cheap and NFC (14 MHz) readers are everywhere.

Letsencrypt was founded 2012, but become available in the wild December 2015. git-lfs mid-2014. So same era in general.

Not only from 0W, but from negative capacity (max charging power) to positive capacity (max discharging power).