“I’m a huge fan of Let’s Encrypt and what they’re doing, but if we want to encrypt the entire Web, we can’t rely and depend on a single organisation to help us do that.”
Most of the web’s free certificates come from one non-profit. If Let’s Encrypt has a bad day, renewals fail and sites go dark. SSL.com now offers free certificates over ACME, joining Buypass and ZeroSSL. Configure a backup CA before you need it, not during the outage.