Comment by capnrefsmmat
6 hours ago
Discussion is included in the Dangerous Goods Panel report, agenda item 4.3 (pages 39-41) and Appendix E (beginning page 89). https://www.icao.int/sites/default/files/DangerousGoods/DGP%...
Paragraph 4.3.3:
> While data indicated that portable electronic devices were more often the cause of fire in aircraft cabins than power banks were, the latter were a significant concern due to their increased use and a prevalence of lower-quality products with defects or vulnerabilities that were more likely to lead to thermal events. Power banks were also not offered the same level of protection that batteries installed in portable electronic devices were provided. The amendments therefore focused on power banks.
Another possibility is that you tend to keep an eye on where your phone and laptop are; there have been some plane fires where people drop a phone into a seat and it ends up getting bent, but at least they notice it fairly quickly. (Will people know the direction if their USB-C power bank is charging from their phone or their phone is charging from their power bank?)