Thanks for the summary. Are there paid CAs that provide tooling like certbot (or work with it)? I don't particularly care about LE or it being free but I like the tools and people using old devices who are easily scared by warnings should be able to use my website...
The protocol used by Certbot is called ACME, and is supported by a bunch of CAs, both free and not.
In addition to LE, there’s other CAs like sectigo, digicert, and Google Trust Services that support it. A few are listed here: https://www.acmeisuptime.com/#CA-Software
