Migrating From Windows Server

I use various different self-hosted services, the arr* stack, plex, homarr, portainer, guacamole, etc.

Some of these are hosted in docker, but others such as the arr* stack and plex in particular are hosted on windows directly. I am very seriously considering swapping from windows server to another operating system due to windows being fairly resource intense.

I feel its important to mention I host several modded minecraft servers and other game servers, and don't have experience using other services to host those server, I typically use a provided exe or start.bat file. My plex library is also hosted directly on windows.

I do have my own domain and most external service access is setup through a cloudflare tunnel as I am on a cgnat.

I work in IT, and if I dont know something I learn very quickly.

My main concern is I look to migrate to another system is data retention, and service compatibility.

So my questions. What operating system is easiest to use for new users, and robust enough for future expansion?

What will I lose and what will I gain?

How hard is it to move these services?

Is it worth moving?

Any knowledge and general advice is greatly appreciated, and if any more info is needed, I will gladly provide it.