I like it, when both USBC charging, and BarrelJackCharging are available. So I can use the BarrelJackAdapter at home for when in "DeskMode", and only need to travel with the USB-C charger, that can also charge all my other devices.
Also makes for the possibility of "Redundant Power Supply", in case you use your old Laptop as a "HomeServer".
Depending on what/where/how I hook up in DeskMode, I also have Power on USB-C. Mainly depends on how/where I want to route DP/HDMI-output.
Also, POE-to-BarrelJack is a thing, while POE-to-USB-C-with-more-than-5V is not.
Yeah, I'd actually use the barrel charger on the road so that it can just live in my backpack and USB-C (provided by an appropriate dock that's connected to a keyboard, monitor, etc) at home.
Also makes for the possibility of "Redundant Power Supply", in case you use your old Laptop as a "HomeServer".