I have an address to register in irrelevant sites and the provider is also irrelevant.
I have an address for important use (utilities' bills, government stuff, friends), currently tuta.
I also have an alias there for occasional registrations.
I'd try proton (has an .onion site) but they force you to supply a phone number or email address on registration, which for me defeats the purpose. They also leak a lot of links to clearnet.
Self-hosting has become increasingly hard but I haven't tried it.
OF course they're more prone to blackouts, and what the study says is that they're less likely to cause severe blackouts than traditional power systems, because they're distributed so that reduces the likeliness; and grids rely on other systems as baseline anyway.
A few thousand people paying $5 per year is not enough to replace hundreds of millions.
...people or dollars? 'Cos i don't think "hundreds of millions" of people are chippin' in, it's Google that's financing "hundreds of millions" of dollars...
But yeah, that target audience is a bubble, normies don't care.
From a recent search i made, with similar purpose, these may support x86 and are based on either Debian or Ubuntu: antiX, Q4OS, Slax; Zorin Lite, LXLE.
(I haven't combed through the results yet so YMMV and there may be cadavers.)
Have you considered Headscale?