For those who own a reMarkable tablet, you can get a similar effect on your suspend screen by running remarkable-news[0]. When suspended, power consumption is very low (idle) and the screen is not powered, making it ideal for static content.
It should be possible to set up an encrypted directory with something like FUSE (though afaik FUSE doesn't run on the reMarkable), though. https://github.com/evidlo/remarkable_entware lets you install fstools.
Using this mode, I was able to unbrick it but it's a complex process so it's not for the faint of heart. It's still good to know that with enough elbow grease, you can always unbrick a remarkable.