That is 2.5A at 5V...not 12V. The 12V is lower, I would guess half with the losses in the converter.
The standard MG wiring is more than up to the task.
Yup, Kiwi Roy clued me in.
I do run a 1200-1500 lumen LED under the fairing nose and for that I just feel better having run new wire for it, all fused separately from the wiring harness. I have the bike cam, the fog lamp and also power the tablet and sometimes charge up the cell phone at the same time so having a margin of dedicated wire going up front just seemed a good idea. I'll be adding yet another cam for rear view.
Also, there is a lithium battery on an isolator and low voltage disconnect and that means it can't make the jump back into the bike's wiring or bad things will happen.