I don't get the impression from this case that US law would behave much differently. This case involved reddit users who had nothing to do with the litigation and were not, themselves being sued. The court saw fit to protect their right to speak anonymously.

In the case of a person making a defamatory post, that person can be sued and reddit would likely be compelled to identify them to the best of its ability.

I remember around the time of the first new "cyberbullying" legislation (around 2016 if I remember right), it was almost immediately used to hinder the Carlton Breweries strike by accusing organizers of bullying and cyberbullying for reporting on scab tactics. It's all very two faced.

Are you referring to the Online Safety Act 2021?

https://www.legislation.gov.au/Details/C2021A00076

Or something else?