If you must always have a copy of your stuff, you must keep at least one copy at home.
I lost quite a few files back in the early days of DropBox. That taught me to never again entrust everything to outside entities. I don't use the Cloud any more. I keep everything on my own server.
And speaking of that, I tried once to create my own email server...so maybe I have to retry that and make a contingency plan, investing in a local server lab and preparing for the worst scenario.
The limiting factor there is whether or not your internet provider blocks the email port (25, IIRC) or not.
That policy was introduced about a decade or so ago to stop email bots spamming the world.
I tried it once too. But that port was blocked by my provider.
Google still, I think, allows you to download your email folders using IMAP to store a copy on your own machine.