I am surprised to hear that. Years ago, I used a system based in Switzerland that encrypted your data at both ends, both before you sent your information and then after they received it. So, it used two keys and it did not have your key. Its servers were also located in safe jurisdictions, including Switzerland. It was protected by the Swiss legal system and claimed that even if a court ordered them to turn over data it could not do so without the customer's key. Sadly, it went out of business. It was so long ago that I can no longer recall the name of the company.Absolutely none of them and I mean none.
Anything private that you want to keep on a cloud drive encrypt it yourself before placing there. Never believe a word about the cloud providers claims to encryption....lol.
Or is it just that you suspect that every company will create a backdoor means of entry?
I used a system based in Switzerland that encrypted your data at both ends