Sorry for nitpicking, but why MicroUSB instead of USB-C in new projects?
Your observation is valid in that USB-C frequently comes with a high power draw for charging batteries. When one isn't using a small solar panel, it's generally better to charge as fast as is compatible with battery health, so that's no bad thing.
But a Kindle which was aftermarket modified to use USB-C would have the same power requirements, just with a durable and bidirectional port. I encourage anyone making a device now to use USB-C, Micro doesn't have advantages and should be deprecated. We'll be stuck with it for a decade+ as it is, we should strive not to prolong the frustration.
Plus it's mechanically flimsy beyond all reason.
USB-C is the one port I'll probably never complain about seeing. I was suspicious of the dynamic voltage selection when it first came out, but it has proven itself to be extremely reliable.
Micro HDMI(And even full size HDMI) are also pretty awful.
now if only apple would update the airpods..
But it's a perfectly cromulent connector, which Micro never was.
There is nothing inherent to MicroUSB that draws less power except that it is older than the standards that allow USB to provide more power (and thus used in devices that don't draw as much power).