I think Square Enix should look into possibly using Easy Anti Cheat for XIV

[Packetdancer]

It's possible to have parts of the running game encrypted in memory, and to have greater protections around especially sensitive parts.

I've never used the problematic waymark tool so I don't actually know how it works for certain, mind you. But were I writing a tool to do that, rather than trying to read things out of memory (which will change from build to build), I'd read what's sent back and forth across the network. A waymark tool might watch and see a series of messages back and forth that are basically "Load Hades EX, connect to instance <whatever>" and then "Waymark A placed at this location", "Waymark B placed at this location", etc. The tool could keep track of this: 'in Hades EX, waymark A at pos1, waymark B at pos 2' and so on. And when you wanted to save the waymarks, it would save that data. Then to put them back, it would just generate the network packets to the FFXIV server as if it were the client: "place waymark A at pos1". So the server accepts the command—it's coming from the right computer, after all—and dutifully sends back to everyone 'Waymark A placed at this location' and everyone sees the waymark appear.

Now, you could probably break the ability to send the commands by putting a sequence number in the packets; if something else uses the next sequence number that the client was expecting to use, you spot that something else has been using your network stream and promptly error out, disconnecting the user. (There's other caveats there, of course. There's always caveats.) But the only way to stop folks reading the network traffic (for things like Teamcraft's automatic inventory updates) would be to encrypt the network traffic, which would have a decent amount of overhead and wouldn't even still be guaranteed to stop it; MITM (man-in-the-middle) security attacks are a thing.

Mind you, that's just a guess; I haven't dug deeply into the FFXIV network protocol. They may already do a sequence number thing and the waymark tool might be handling setting things differently. I'm speaking from the standpoint of "I used to be a video game developer for my day job, saw various shenanigans, and hear from former co-workers and various friends still in the industry about the shenanigans they see", and assuming these shenanigans are not appreciably different than many others.

At any rate, I think if SquareEnix is forced to crack down on mods from an engineering standpoint, writing things to prevent them entirely, it'll introduce new annoyances and inconveniences for everyone else, because that sort of security is never free. Not in that sense. So, y'know, I'd personally prefer they not.

But if the mods truly become enough of a problem to merit it... well, maybe that'll be the price we pay.