Discussions of IP hiding techniques have been forbidden here for as long as I’ve been around.
See this for example from 2002:
If you use a VPN to access the SDMB we’re not going to immediately ban you, so that’s a bit outdated.
VPN has a lot of legitimate uses. I use a VPN to connect to work, for example. I have tried in the past to allow discussions of VPN services as long as discussions of the “hide my IP because I want to evade bans and do illegal stuff” type services were avoided. Unfortunately, those discussions didn’t go well, with too many folks implying what they wanted to say instead of outright saying it (so that they wouldn’t technically break the rules), and effectively the forbidden aspects of the topic were discussed.
VPNs are now being advertised heavily as ways to hide your IP for things like file sharing and ban evasion. You can use them for legitimate uses, but that’s not how most of them are advertised these days.
Because of this, I’m not as lenient as I used to be, and I’m going back to the old blanket “you just can’t discuss this here” approach that we used to have.
The folks who do have legitimate uses for VPNs are, unfortunately, just out of luck.
Similarly, there are actually some valid and legal reasons for using torrents and file sharing, but discussions of those are forbidden here as well.