it can't be deactivated like previous versions.
It can but it's not that easy.
I've known opera.com's download page to hand off download requests to 3rd party hosts (including edu's etc.) - hosts of which I know nothing of, nor how clean these 3rd party systems may or may not be.
Well, in theory we don't know anything about any host unless we run it.
Those hosts are used to avoid Opera Software's servers to face issues because of heavy traffic and also to allow the user to download from a nearest location, what brings better download speed. And they are supposed to be clean.
Afaik autoupdate does not use third part hosts/servers.