I thought the article was completely unconvincing. Like, COMPLETELY. The author's arguments against Let's Encrypt don't hold water. Argument #1 is that "The more sites secured by Let’s Encrypt certificates, the bigger the threat surface becomes because the compromise of Let’s Encrypt’s KMS could potentially affect a large number of sites." Fine, but that's true of EVERY certificate authority. If you get rid of Let's Encrypt, that's one FEWER CA, so that's more consolidation, not less, and more certs being handled by each of the other remaining providers. Argument #2 is that LE has "no skin in the game," because they're a nonprofit (ISRG) and their certificates are free. This is ridiculous; the EFF, Cisco, Mozilla, and Akamai, among others, are the members of ISRG, and all stand to sustain tremendous reputational damage if LE is compromised. Moreover, it's the FOR PROFIT certificate issuers (most notably Comodo and Symantec, but they have lots of company) that have historically been the problem, precisely BECAUSE they're for profit - they've been issuing all manner of dubious certificates, because they get paid by the certificate. You don't need to look very far to see that they've both been de-trusted.
Google announces plan to distrust Symantec SSL certificates Bogus SSL certificate for Windows Live could allow man-in-the-middle hacks Argument #3, as best as I can even figure it out (it's really incoherent) is that "If a site certificate is revoked, and no one is paying attention to this possibility, traffic will drop precipitously and you as a business person may well be no the wiser for why your lead generation dried up. " But a certificate from LE is no more or less subject to revocation than a cert from any other issuer, and if your cert is revoked and you don't notice, you're a total moron (or an Equifax employee, or both): Everyone going to your site will get a message from their browser saying that the certificate is no good. Surely some of them will report this to you, if you don't figure it out yourself.
I get the feeling that the author is, whether he knows it or not, a tool of the paid certificate issuers.