Music collection is typically “write once, read forever”. It’s hard to estimate the lifetime of such read-only SSDs, but it’s measured in decades, if it’s regularly powered on and read entirely. If it’s not powered for years, you’re going to risk data loss due to thermal noise flipping bits randomly beyond the built-in ECC capabilities. If you keep it powered on, you still need to regularly scrub it (i.e. read all data) to force the firmware to fix and write back flipped bits. Some firmwares may do this periodically by themselves, but it’s a black box, so you must do it yourself to be sure.

I wouldn’t recommend relying on a single drive for long-term storage of anything that’s worth more than ~$1000 - neither with SSDs nor HDDs. Freak accidents can happen with any component. You PSU can go rogue and fry your SSD, etc.

The best option is most likely a single local drive with continuous mirroring to a cloud service. The drawback is the ongoing cost of the cloud, and the possibility of partial data loss, because cloud mirroring won’t be instantenous when saving bulk data.

A local RAID1 array is cost-efficient, but doesn’t save you from black-swan events like floods or house fires.