At this point I am really only interested in lights with USB charging. It just makes sense. I am leaning towards a philosophy that a light must either take primary cells, or feature onboard recharging.
We don’t charge our cell phone or laptop batteries outside the device anymore. (I would always want removable/replaceable common batteries however, unlike most modern consumer electronics.)
As someone said above, the issue is in implementation. Many companies need to improve how it’s implemented. Only a few do it right.
When done right it adds little or no more bulk and minimal complication. Hell most 18650 lights already have wasted space or superfluous material bulk equal to or greater than what USB charging would require. It’s a matter of design.
Look at the new Thrunite T1, it’s smaller than most 18350 lights and has USB.
False. Almost never has such a requirement. And if so that is an engineering choice and not a mark against USB charging.
You don’t need proprietary cells to have USB, so point is mute.
See above.
It doesn’t have to, again that is about engineering choices. See Eagle Eye X2R mods here.