...for 5 or 10Gb of additional storage. 😀All Mac with Thunderbolt. You can use a Thunderbolt 3 to 2 adapter, then the Thunderbolt to FireWire 800. And with Sequoia, it's possible to sync the first iPod like that
By the time iPods had significant storage, you could use USB to connect them. Nearly every phone in the last few years has had 128 Gb at least.