There's a recent phishing campaign with sites hosted by Cloudflare and spam sent through either "noobtech.in" (103.173.40.0/24) or through "worldhost.group" (many, many networks).
"noobtech.in" has no web site, can't accept abuse complaints (their email has spam filters), and they don't respond at all to email asking them for better communication methods. The phishing domains have "mail.(phishing domain)" which resolves back to 103.173.40.0/24. Their upstream is a Russian network that doesn't respond to anything. It's 100% clear that this network is only used for phishing and spam.
It's trivial to block "noobtech.in".
"worldhost.group", though, is a huge hosting conglomerate that owns many, many hosting companies and many, many networks spread across many ASNs. They do not respond to any attempts to communicate with them, but since their web site redirects to "hosting.com", I've sent abuse complaints to them. "hosting.com" has autoresponders saying they'll get back to me, but so far not a single ticket has been answered with anything but the initial autoresponder.
It's really, really difficult to imagine how one would block them, and also difficult to imagine what kind of collateral impact that'd have.
These huge providers, Tencent included, get away with way too much. You can't communicate with them, they don't give the slightest shit about harmful, abusive and/or illegal behavior from their networks, and we have no easy way to simply block them.
I think we, collectively, need to start coming up with things we can do that would make their lives difficult enough for them to take notice. Should we have a public listing of all netblocks that belong to such companies and, as an example, we could choose to autorespond to all email from "worldhost.group" and redirect all web browsing from Tencent so we can tell people that their ISP is malicious?
I don't know what the solution is, but I'd love to feel a bit less like I have no recourse when it comes to these huge mega-corporations.