What is the best practice If I want to have 2 or more copies of my files, each copy in a different cloud storage? meaning i am not trusting the single cloud strategy
I recommend a 3-2-1 backup strategy.
See here (or many other sites) as explanation.
Please keep in mind that cryptomator is not a backup solution. You’ll need to find a backup solution that fits your needs.
I am using this since years now:
appreciate the light shed