So I just buy external $200 USB hard drives.
There is a market for something lower latency, higher capacity, but pay as you go (no upfront cost).
Frankly I wouldn't mind some sort of giant disk drive, vinyl record size, if that makes sense and is lower cost/TB.
Basically you have a nextcloud instance that you fill up with your data, then you ask for an LTO tape to be written with it. Repeat ad infinitum.
The tapes are yours; when you buy a tape it comes with 3 free operations (read, write, checksum control). If you want your tapes back, we'll mail them to you, else we keep them in storage for you.
As the tapes are written using LTFS, you can easily read them back anywhere with the proper drive.
You only pay a fee for the cloud storage; it also gives you access to your archive's database (what file is on which tape, etc).
We also implemented the ability to turn off entirely (cut the power) disk chassis when unused, to save power (using 60 or 102 drives chassis). So if you have enough data (a few hundred terabytes to petabytes) it can make sense too.
The modern tape drives are miracles of precision and the tapes are these cool little cartridges but why? The meat and machines handling tape carts liked the of 3/4in format just fine. With modern electronics for the write heads and slightly less ruinously expensive loading and running hardware we could still get decent data density, even if we have to hunt for the tracks each tape load.