I found 1fighter2defenders and it is a survival server that tries to stay as vanilla as possible.
It has no gameplay rules and no admins running around to stop you. There are no land claims and no protection so your stuff can get raided or griefed anytime.
Building griefing cheating and pretty much everything goes. They also say there are no server sided dupes and there are no world resets.
The server started in April 2021 so it has been around for over 4.5 years and it has had thousands of players join at least once.
It runs on 1.21 and it lets players join from 1.17 to 1.21.11.
