I found Rosedalean SMP and it is an 18+ Java survival server on 1.21.11 with an enhanced vanilla style. It feels made for both casual players and hardcore grinders so you can make a huge mega base or just build a cute house and chill.
It uses add ons so you do not have to mess with big mod downloads. There is an interview and approval process to keep trolls and griefers out so the community stays welcoming.
There are community run events plus weekly game nights on Sundays. You can join factions or start your own and there is a shopping district where players buy and sell items.
It also has Simple Voice Chat Terralith biomes a ticket system for help and BlueMap so you can see the explored world.
