My Plex story - long read - sorry

I bought an Asustor NAS to back up my computers on my home network. Then I discovered all the other things this box was capable of, including becoming a Plex server. I installed Plex on my NAS and I had an external hard drive with videos that Plex was serving. I was in heaven. I never knew something like this existed. It was amazing, while it lasted.
On February 21 I noticed the drives in my NAS were just grinding away for no reason. I logged on and got the shock of my life. My files were being encrypted by deadbolt. I freaked and unplugged the NAS from power and the network. I started researching.
I got over it, and I repartitioned and reformatted my drives and I got rid of deadbolt. I rebuilt my backups and I am fine. I isolated my NAS from the internet. Only LAN connections now. I closed all the open ports.
But now a week later I really miss Plex. I salvaged an old computer and upgraded the CPU, added ram memory and I bought a 500gb ssd. I have spare HDD’s so my little computer has a ½ tb ssd for the operating system and (2) 1tb hdd’s for storage.
I downloaded and installed TrueNAS Core a few times and it could never find the operating system. I tried TrueNAS Scale. Same thing. It went through all the motions but could never find it’s operating system.
I had a memory stick with an Ubuntu installer so I tried that. Ubuntu found itself and all the little things in my computer and even found a networked printer.
So there was nothing wrong with my computer. There must have been something wrong with the TrueNAS installer.
I repartitioned and reformatted all the drives and installed Windows 10. After it was all done updating I installed Plex. I have the (2) 1tb hdd’s for media. At first I had remote access turned off but after a day or two I turned it on. So now I have Plex running on a Windows 10 computer. Again, I am back to amazing. But I have some concerns.
I am a little gun shy now and I don’t want a repeat or worse. Has Plex ever been hacked? Can a hacker break into my computer through Plex? And then my network and other computers? I left the Plex ports alone. Should I change them? If I do change the ports do I have to change something on Plex on my phone? What else do I need to know? Any help and guidance will be greatly appreciated. TIA.
Old-Steve

I have not heard anything. Since you tried True Nas, you might try Unraid Nas. I have been running it for years with Plex running in a docker container and have not had any issues.

Thank you for replying.
Is unraid nas more secure than windows?
I’m just nervous about getting hacked again.