> laws only apply to large players, e.g. >1M users.

What if I don't want to share my user list with the government?

Then don’t run a content site?

What if I don't want the government to know I'm a user of Yahoo Answers?

Don’t connect to any ISP?

You don't have to. You can self report and if you incorrectly report it is a crime. As simple as that. This is also exactly how the definition of very large online platforms (which is a site from 45+million montly active Users) in the EUs new Digital Services Act works [1]. Some companies (primarily porn) are believed to have misreported, and are being investigated for that[2]. If they are found guilty they will have to adhere to the regulation for vlops, and pay a fine of up to 6% of their annual EU revenue... (Obviously not the full sum for a first time offence) [1]https://en.wikipedia.org/wiki/Very_Large_Online_Platform [2]https://www.politico.eu/article/online-porn-websites-europe-...

On top of that, your shareholders will want to know the actual number of active users.

Couldn't the government claim you are lying about how many users you have, and then demand you show them how many you have? How will they prove how many users they have without handing over the list of users?

Theoretically, if your forum is like Reddit they can just crawl the site and look for usernames that appear on top of posts.

But I'm sure there are other ways.

>It's not like nobody would ever build another forum if there were laws like the ones proposed by GP.

Won't they just build the forums in other jurisdictions then? How many European forums do you frequent? I barely visit any.