You will always get attacked through the weakest link and it has been well-described how dangerous securing unencrypted wallet backups in the cloud are. It doesn't matter if the service has end-to-end encryption; this only stops the company from accessing your files. Anybody with your pCloud login was able to download your wallet, including possibly a seed phrase if you included that.

If you are going to store backups in the cloud you must always encrypt the file (or text) with an encryption format yourself - I prefer using GPG with an extremely long diceware passphrase and a 4096-bit RSA key.