SDcards are said to die often/easily in Raspberry Pis. I heard someone say they die when there's a write access going while the Raspi is taken from power. Is that true? That would mean running a Raspi from SDcard is fine as long as there is no write access happening, which can be done by enabling readonly (root) filesystem.
I have had a few cards go but I never isolated the cause. Certainly unceremoniously cutting power occurred a few times.
I got tired of the inconvenience of having to rebuild the Pi installation and flashing SD cards, so now I boot my Pi4 directly from a USB attached SSD, no card on-board at all. I haven't looked back. Others seem to also be getting good result like: https://www.jeffgeerling.com/blog/2020/im-booting-my-raspber...
From what happened to me - cards die, especially older ones when there is a lot of data written to them even without power failures (UPS ensured that). And when you have a journaled filesystem there is a lot of writes.
I made hybrid systems where either the card is only used to boot the system and everything (root included) is loaded from a USB drive or where card is mounted R/O, there is small ramdisk for volatile data and only when upgrade/reconfiguration is needed you remount it r/w, do what you need and then remount it back r/o. In both those setups cards didn't fail for the last 3-4 years. With a standard SD card root-fs they lasted about 4-6 months.
Can anyone comment on that?