I found HimasSMP and it is a true anarchy survival server on 1.21.11. There are no rules at all so people can build or grief or raid and just do whatever.
It has an economy where you can grind and trade for money. You can use shop and sell plus an auction house. You can also set homes and teleport back to them.
There are shards you can collect while playing and you can use them to buy spawners. That means farms can get really strong if you keep at it.
It also runs GrimAC anticheat and Simple Voice Chat. They also say it has anti redstone lag and the survival is optimized. They also say it is not pay to win.
