I found this server that is a hard survival world with both Java and Bedrock players together. It runs on the latest Minecraft version and even has backwards compatibility so it feels pretty updated all the time.

The server is no grief so people actually protect their bases. You can claim land with ProtectionStones and use homes and sethome and tpa to get around. There is also random teleport in the overworld so you can find a spot far from spawn and build in peace.

There are custom enchantments and you can put leads on mobs to teleport them which is actually super helpful. Every Sunday they let you fly for free in the overworld so building and exploring is way easier on that day.

They have a bartering based economy with server shops and a public market and some tutorial warps so new players do not get lost. There is also a main PvP arena with keep inventory which makes fighting less stressful.

The staff feels pretty responsive and there is Minecraft and Discord chat linked so you can talk to people even when you are not in game. On Discord they even try to help with homework which is kind of funny but nice if you are still in school.

Overall it feels like a chill but challenging SMP where you can play survival on hard difficulty hang out with people on voice and not worry about griefers.