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 IPRainbow Unity SMP Rank Up Survival
Rainbow Unity is an SMP that is updated to 1.21.11 and it is built for people who want a place to settle in.
You can claim land so your stuff stays yours and you can build up an empire over time. There is also a rankup system with perks so you can keep leveling up while you play.
I also saw crates for powerful rewards plus daily rewards to keep you coming back. It has ranks quests custom items crates and land claim so there is always something to do.GG.MINEWIND.NET New Server IP