I'm still using a Sandisk 8GB microSD from 2008 running 24/7: smartphone expansion 6 years -> Orange Pi as a router for 3 years, Pi 4 running Frigate for 3 years.

I'm guessing it's SLC/MLC.

Had a Transcend 32GB in 2016 die after a year.

The biggest issues with set-and-forget setups is software upgrade for security or other reasons, jumping major versions ends up breaking things. Compared to cloud which is (usually) regularly updated.