You could argue that The Don in charge of the US is in control of letsencrypt
A simple windows to linux migration is not enough. If certificates expire without a way to refresh you'd either need to manually touch every machine to swap root certificates or have some of other contingency plan.
He's not in control of letsencrypt or any other US-based CA.
It may not be well known, but Trump's administration loses about 80% of the time when they've been sued by companies, cities and states.
There's much more risk of state-sponsored cyber attacks against US companies.
It would be nice to at least have a very high level contingency plan because in worst case I won't be able to google it.