It's not really worth it, even though I'd commend the OP for wading through the WoL stack. I have a NAS that's running 8 drives and a modern Intel CPU and it runs around 40w from the wall under load, and idles <10W with the drive spun down and CPU not doing anything. The WoL setup made more sense 5-10 years ago when power save functionality was much more primitive and drives were way less efficient.
It's also a solved problem for the vast majority of the population. You pay Apple or Google a few dollars a month and they handle backups for you. Those servers aren't sitting idle 99% of the time waiting for you to backup so there is no wasted power. Self hosting is fun but not the most practical option. And now iCloud has end to end encryption, there is little reason to bother doing it yourself.
This is only because the vast majority of the population agrees that it’s a reasonable tradeoff to not bother with all the digital privacy and security stuff beyond what the defaults are and just go on with their lives. The reason behind this is that almost no one is significantly negatively affected by not being vigilant and self-hosting everything. The downside is that things like PRISM can exist and nation-states and any sufficiently powerful or skillful interested party can and do far more easily target, surveil and harm any individual they want. Again, those individuals are not your average Joe so the public doesn’t care. As long as you don’t leave the herd and stay in line, you’re safe. Personally, I didn’t give any f… about privacy until I felt there’s a good possibility US agencies can target me, due to things I would start to talk about online. Those things were not illegal neither in US nor in my country, just different ideologies from the status quo of modernity, but I knew for a fact people have been (illegally) arrested by US agencies before due to voicing similar things.[0]
