Just because something is free, doesn't make it better. And having 12x more points in same timeframe where the automated renewal can fail, certainly doesn't make it better statistically.
Also i grew up with the notion, 'nothing in the world is free, except the sun'. So i wouldn't be surprised if they will start to monetise this LE user base at some point in time.
I have my certbot set to run once a week with --keep-until-expiring, so it will try to issue a new certificate when the old one's remaining validity is less than a month. I could also set it to run daily, because it doesn't actually do anything if the cert is still valid for long enough. But a week works on my (admittedly small) scale.
So unless you're experiencing a multi-week DNS malfunction or multi-week DDoS (in which case you're in some deep shit anyway), you should be fine.
Is this really what i am reading?
Professionally, it's not once every three years, it's that x the number of clients we host. Which is a lot. Many are clamoring for LE, because it's within their budget: $0. So yea, I want to automate that.
Edit: Also, it's a persistent myth that certbot needs to run as root. It most certainly doesn't on my servers.
Fortunately, we can also discard some of the high stakes gambles we take to avoid cert costs. Your cert lives for 90 days. Why wait until day 89 to renew? It's certainly not to avoid the expense. The LE defaults renew at day 70. That gives you 20 days for transient failures to resolve themselves, so that's a concern you can dismiss out of hand. And if you don't think that's enough time for ops team to work out whatever problem they have, you can configure your tooling to renew sooner.
Yes, renewals every 70 days introduces a 5th renewal every year, but IMO the hardest and most important renewal is the first one, and you might as well take it sooner than later.
TANASTAAFL is a thing, but even if the only lasting impact LE has is to arm-twist CAs into a commonly accepted API, that's still a win in my books for competition and near-frictionless competition. Anyone seen the Comodo API? And how it compares to the Symantec API?