There’s been some discussion about this in Discord.
I use Tresorit myself for encrypted file sync and obsidian plays nice with that (on linux anyway I don’t have a windows setup to test it on)
pCloud isn’t bad, if you want encrypted sync.
So to secure and get sync with Obsidian. Im using https://cryptomator.org/ to create a secure vault in my Dropbox drive and save my Obsidian vaults there
I have been using VeraCrypt for 5 years and I very happy with it. I can recommend it.
I’m not sure that Obsidian’s future sync service will support encryption.