Hi brenz3,
welcome to the Apple (user-to-user) Community!
Re: "How to transfer music from an old iPod to iPhone or Mac"
Am no expert in this area, yet your request surely deserves some response.
At the least we get the discussion under way, and someone with the know-how may join in.
It is not easy to guess whether the iPod Classic is compatible with your iPhone and / or Mac:
eg: wondering which iOS version is installed on the iPod.
also which iPhone model and iOS version you have
and which Mac model (year) and MacOS version you have
See how to: Identify your iPod model - Apple Support
See this discussion thread on a similar topic: How to move songs from iPod to iPhone - Apple Community
Most of the available Apple info seems to be for iPod Touch: (you can choose the iOS version at the top)
For iOS 12, 13, 14 or 15: Transfer files to iPod touch with iTunes - Apple Support
and
For iOS 13, 14, or 15: Use AirDrop on iPod touch to send items to nearby devices - Apple Support
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Re: "Is my music locked into this primitive device forever?"
Other things you may or may not be able to do:
For iPod / iOS 15: Wirelessly stream video, photos, and audio from your iPod touch to a Mac - Apple Support
How to: Back up and restore your iPhone, iPad, or iPod touch to your Mac or to iCloud - Apple Support
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There is an iPod Classic user guide available for download at: Apple - Support - Manuals
(I don't know whether it is for the model you have, or if it has anything useful for your needs.)
and
There is an Apple iPod discussion community online : iPod - Apple Community
All the best :-)
