You're right. SD lacks things like overprovisioning and wear leveling that would reduce failure rates. It's also rather slow to read/write from. On another note, it's incredibly easy to lose them.

It is always a bad idea to store any amount of important data on a single medium.

Seen too many (including myself at some point) have all their data in one external HDD and pass it around friends with a caution to be safe with their data.

I've lost most of my photo and video collection due to two HDD failures between 2017-2020.

SD cards for me is just a medium to transfer from a device to permanent storage so I don't have to worry about data retention on a tiny device unless it get lost.

You can raid 1 it and backup right?