Same for digital.
> With digital, you can easily just have thousands of copies spread around various data centers and never have to worry about that.
Same with print. Just replace "data centers" with "libraries".
> The low cost to copy and the ease of transfer are pretty big advantages here.
It's only low cost and easy if you assume the whole computing infrastructure is already available: electrical and networking grid(s), working equipment, compatible software, trained operators, etc. All of that is expensive and, for archival purposes, fragile.
> And you get things like easy searching, perfect copies, etc as well.
No arguments there, but these advantages have little to do with long-term preservation.
The best archival strategy is going to involve multiple types of media. Keep things available on the network for ease of access. Put important things on paper/parchment just in case. Mix in tape/film and other media as needed.
You originally said "you don't even need to destroy them to render them useless. Just turn off the power!" I guess turning the lights off makes a book "useless".