Facebook and other social media platforms simply hand their data over to the government because they want the government to do them favors. DU doesn't operate on anywhere near that scale, and so I would argue that the risk is considerably lower. Even if such a demand were made, the EFF or the ACLU would likely jump at the chance to defend a private American business against the government's demands for its user data.
Could the government try it anyway? Sure, but it would be a very large amount of effort in exchange for what would be pretty paltry amount of information. When you register at DU, we ask for a username -- which the vast majority of people create as a pseudonym, without giving any hint of their real identity -- and we ask for an email address. This email address can be a throwaway email address -- as long as you can receive a password to it, then you can join DU. We also have IP address information which can be linked to a username/email address combination.
So in order for this to be of any use, the government would have to go through a court case, or series of court cases, which they are likely to lose, and if they win, they'd get a list of IP addresses which can be used to tie a pseudonym and an email address to a vague geographic location. It would be an insane amount of effort for very little return.
Alternatively, they can just shake hands under the table with Facebook and all the other social media sites for free, and get millions of people's real names, addresses, phone numbers, occupations, education histories, medical conditions, photos, videos, likes, dislikes, friends, families, etc. etc. I think it's far more likely that they will just stick to that than bother with DU.
In addition, moving to the dark web would create the following problems:
1) No advertising revenue, which means no money to run DU. Star Memberships do not bring enough money in on their own. And even if they did...
2) Nobody would be able to find DU. You can't search up dark web sites with Google or DuckDuckGo, and you need special software to get there, which most people don't have and aren't inclined to want to learn.
3) It would make DU look like an actual risk. Democratic Underground is a legitimate business, operating in the open, exercising our First Amendment rights. Sites operating on the dark web are basically putting up a flashing sign saying "Hey, we're criminals." Why do that?
I understand that these are difficult times and people are concerned about this sort of thing. I offer this up as something I hope will help people to worry less.
Edited to add: Er, if you're a social media user it might not help you worry less. The point I'm trying to make is that if the government starts mass-imprisoning and interrogating people based on what they do online, they're not going to start with DU because they have all of social media at their disposal. Currently they are not rounding people up in this manner, and hopefully that will remain the status quo.
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