It's true that certbox is very easy to install and single run on stable machines with full command line access. Then a lot of Paas providers pre-package a let's encrypt feature to allow for simple setup of SSL cert (as simple as checking a checkbox most of the time)
Now certbox in itself is not really simple in my opinion, and one feels it very fast as soon as we fall out of the beaten path. For instance having it run for volatile instances isn't simple, or if the Paas misses the single feature you need (ex: wildcard support on heroku) you'll have to bear all the complexity again on your shoulders.
In particular the base principle is to renew the cert every 30 days, so inherently proper automation and error handling is the first barrier to entry for certbot. That's already a bit further than "a few commands" in my opinion.
The point isn't that it is particularly difficult (if you know what you are doing). The point is that from a cost-benefit perspective, it probably isn't worth more than 2 minutes of your time, if that.
