My thought process is that the majority of modern hardware/software RAID solutions don’t do error correction properly. And even assuming something that does actually do checksumming and such semi-properly is employed, I think if we are talking tens or hundreds of years from now, it’ll be nearly impossible to find a compatible hardware card should the ones in use die.
I’m aware it already sucks trying to build a project six months in the future, let alone six or sixty years, but perhaps something purely software-based that does care a ton about integrity, like ZFS, would be the best bet in terms of long-term compatibility of a hard-drive storage solution.
So long as the drives can still be plugged into a system, any system, and even if OpenZFS eventually drops backwards compatibility with the version used to create the pool, it’ll likely still be possible to virtualize whatever version of Linux/BSD/Illumos is compatible with that particular version of ZFS and then import the pool.