The server is missing these mods, remove from client to join this server?? Why is it server sided now?

1.20.1

Forge, so its discontinued? Big sad

Update the mod

I seem to be on the latest version, but thank you anyways

Hello!
Are you using Forge or Fabric?

As far as i know, Forge version is maintained by the community and needs version on both side.
Ir you want to be able to play with client side only, you can use the fabric version.