My Raspberry Pi, on which I host a Minecraft server, suddenly froze. I cannot not SSH in, nor can I join the Minecraft server. I ran the Minecraft server in Docker, via itzg/docker-minecraft-server. I turned off the Raspberry Pi, took out its microsd and plugged it into my PC, to at least attempt to run the Minecraft server from my PC to see if I still have the data. I tried to copy it with cp, but I got an input-output error. Could this be the filesystem's fault? And how can I fix this? If you need any additional info about this crash, please do not hesitate to ask.
MicroSD cards aren't designed for a lot of writes. Your card it probably dead. If you must use a RPI with a SD card you should get an enterprise grade MicroSD
While I haven't personally tried it, I've heard people have issues with cooling when using the M.2 hat, especially when using their Pi for intensive applications (like hosting a Minecraft server). I'd honestly recommend just getting a 2.5" USB drive enclosure and an SSD. Costs about the same amount of money without the drawback of poor cooling. You can use it with any case, since it just connects via USB. I have been running my Pi this way for years (in fact I have never used an SD card in it).