I don’t understand the “yes - but” combination. To be clear, systems in LXCs tend to do lots of writes, wearing down (parts of) the flash after some time. That’s why it’s strongly recommended not to run them in Omnia’s internal flash, over long term at least.
What I meant is: yes - I used LXC containers but on an external SSD card. There was an instruction how to remove one Wifi card and put it on another place and put the SSD card inside. The default config was in a way you could add some LTE SIM card as fallback. I did bought a mSATA SSD and deployed LXC containers there.
But this card was not affected with the problem. The problem was the internal flash (where I did not deploy any containers).
I wouldn’t be so sure. We don’t know, how he has it mounted and if he wasn’t using Storage plugin, which is in Foris, it could happen that it couldn’t find mSATA SSD and then it was writing to eMMC.