I wish there was a way to donate money towards a fund - like, give $100USD, that goes into some index fund, and then LetsEncrypt withdraws $3.50 (as per https://www.bogleheads.org/wiki/Safe_withdrawal_rates ) a year until the sun burns out. I'd much rather spend my money knowing its a small ways toward making this kind of thing self sustainable.
Now build a product around that idea, and be the next patreon. I heard of this great company that'll help you get ssh certs for free.