IMHO I think from version 5.10.0 the path won't change again because generic node names have been around since then. Therefore, the same DTBO can always be applied. But as long as the hardware setup doesn't change, there's no reason to ever change the DTB. Therefore, after an update, restoring the DTB from a persistent location would also be an option.
But I guess you will have more fun to keep having the boot.scr magic in place. And tinkering with boot.scr magic opens even the option to load the DTB from the persistent location direct or choose a different DTB file name that wouldn't be overwritten.