You folks are talkin' about USB ports in NEW cars, here!
Starting last summer, I posted a thread (or two or three . . ) about my "MP3-player" project. It communicates with the 1995 OEM digital radio receiver as an FM transmitter. It has a bluetooth receiver as well, and two USB ports. I, too, use a 64GB Sandisk Cruzer Fit, and I think I've filled up 60%. I created folders for "Rock&Roll", "Classical", "Jazz", "Folk" etc. Then, organized the folder by Artist, and those folders broken up into Album subdirectories.
The MP3 player device was meant to be plugged into the cigar lighter, but people complained about unreliable power connections. I bought a cigar-lighter splitter, cut the wire to one female plug, and connected the player (semi-) permanently to its own fused ACC lead. It's a $30 device! From Jhina! Works great. It will play MP3 and WAV files. Won't use FLAC. But -- no big deal.