This article explains it very well. Its about SSDs, but it also counts for (micro)SD as it counts for flash memory/storage in general.
The article explains it very well. Consumer-grade flash has far less write cycles. Compare with commercial-grade; these are already much better. SLC is very expensive, but (a)MLC is affordable.
Also, because of complex firmware, filesystems sometimes get bricked after a power loss (which is solved with a data recovery + a format). But that does not normally happen on a smartphone.
The article is ‘old’ in that it does not mention QLC. Its even worse than TLC.
Still, even the bad TLC/QLC is usable for some purposes. If you only write to it once and then keep it like that, such as a music collection, then you’re good to go. Logs (RPis!) and cloud data, not so much though. I even had a consumer-grade SSD with Docker on Windows going from 100% to 90% in a few months, so gotta watch out with stuff.