I found a survival server called MinecraftOffline that runs on version 1.21.11 and it is based in Finland so it should feel smooth for European players.
The big thing is the world is permanent and they say there are no resets so your builds can stay for the long run.
It also uses custom written plugins to make gameplay feel different and more unique than the usual survival experience. The server also talks about having reasonable hardware so it should run steady.
EU No Reset Survival With Custom Plugins
GG.MINEWIND.NET New Server IPFresh EU Survival Network Germany
This is a new Minecraft network hosted in Germany and it feels really clean and simple. It is all about classic survival with no extra weird stuff.
There are five Paper vanilla survival servers and each one is its own world. You can pick any world you like and just start building. You can also hop between worlds if you want a fresh start or to play with different friends.
The servers are free to play and there are no ads and no paywalls and no gimmicks. Each server is set for up to 20 players so it feels like a small chill community instead of a huge messy one.
The owner wants the network to grow and if more players join they plan to add more servers so everything stays smooth. They also listen to ideas in the discord so players can help shape how the network goes.
The whole thing is aimed at EU players since it is hosted in Germany so your ping should be good if you are in Europe.GG.MINEWIND.NET New Server IP