Maybe I'm completely wrong about everything I'm going to say and in that case we can laugh about this theory I guess but here it goes..
Most people are only worried about if the VPN provider is keeping logs or not. But even if they don't keep logs you could still be tracked by anyone who can see incoming and outgoing connections to the VPN server.
This would be easier to explain if I drew some images but I hope you understand anyway with just text. What it looks like for these adversaries is:
- they know your IP and who you are.
- They see you connect to a VPN server.
- They see VPN server connecting to many different servers and they don't know which one is you.
But when it comes to number 3, they could actually figure out which one is you.
Obviously, if you are the only person connected to the VPN server they will see that there is no one else besides you using it and then any outgoing connection from the VPN server must be you.
If there are just a few users. Maybe three users are just connected to the VPN server but not doing anything, just idle. Another user is spending time reading reddit. Then you connect to the vpn server and within a minute a new outgoing connection from the vpn server starts and goes to lemmy. Pretty good guess that is you from their perspective. And to make the guess even better, when the connection to lemmy ends, you decide to immediately end your connection to the VPN server. I'm confident this would be enough evidence in a court and then it's definitely enough for data harvesting and mass surveillance.
All this analysis can be done automatically with AI, even if there are hundreds users on a VPN server, the AI will over a larger amount of time (not just hours but days/weeks/months) collect enough data to be able to profile users and make good guesses which domains you are visiting even if the VPN prpvider doesn't have logs.
What is the solution to avoid this type of tracking? Tor baby, tor. Leeegggoooo Whonix!