Imagine going from a small community to growing large enough that Disney forces you to close up shop. This is exactly what happened with /r/MarvelStudiosSpoilers.

Here's an excerpt of what the subreddit's shared /u/MSSmods account had to say about the closure:
This subreddit started very small...I ran it alone, then I added some mods, then those mods left or lost their minds...It was along time ago (to me) and I actually do not remember all the details anymore. Eventually, I was able to get some reliable/responsible help for a page that was never meant to be a serious thing. It grew and grew...now it has grown so large that people from the MCU know of it. Sadly, this means Disney also knows of it. The Mouse always wins...a lesson I learned from South Park.
The group then said that anyone who'd like to take over the subreddit, including "all the legal ramifications" can message the shared account.
The said statement is no longer available now that the subreddit has become a "private community" and effectively shut its doors from everyone, potentially forever.
Disney is looking for the culprit behind the leaked Ant-Man and the Wasp: Quantumania script, which initially appeared on Google before finding its way to the Marvel Studios Spoilers subreddit. Both instances were met with a DMCA takedown notice, but Disney insists on finding out who shared the script. Specifically, the Mouse House is pointing to the user /u/MSSMods, a shared group account that moderates the said subreddit.
Because it's a shared account, it's difficult to link back the script to a single user. But, this hasn't stopped Marvel from requesting the "name(s), address(es), telephone number(s), email address(es); (b) any IP address(es) used by such user; and (c) account number(s)" of the "Infringing User".
In addition, the DMCA subpoena application is requesting details from users active on /r/MarvelStudiosSpoilers around the same time the script went viral.
We're curious to find out what will happen once Disney can identify the culprit. The end of the search could also mean the end of Disney's legal action. But, Disney might make an example out of someone to prevent similar situations.
Speaking of Ant-Man 3, the third Ant-Man film didn't fare too well at the global box office in subsequent weeks. After the film posted a franchise high weekend take, Ant-Man 3 became the worst-reviewed MCU film ever and is now on track to post lower numbers than its predecessors.