Was really interested in reading this perspective, to be disappointed by a Medium paywall. A shame, as it seems like a contrarian point of view.
They're worried that LE is a big target for hackers since getting their keys would compromise such a huge number of websites. Also they wonder if LE is sufficiently motivated to protect those keys, since they are a non-profit and don't offer breach insurance, and don't stand to lose a lot of money. It wraps up by encouraging site owners to review breach insurance options offered by their CA or cyber insurance from some third party.