You get the problem with the title ID when dooing a factory reset or uninstalling the DS game when using CBHC. But the user would know he did that. We (as the community) know that, that's why @GaryOderNichts created that option in the recovery menu.
But if the error suddenly appears or after a long time of storage without doing any of these things or not even having CBHC, then you obviously can't be that problem.
Here is a link with people having the hardware problem: https://hackmd.io/d12Fq9g-QlCjN2HJp7Yvew?view
I have two consoles with an bad eMMC, maybe even 3 but I have to look into that one first.
2 of the systems were unmodded, vanilla Wii U's that have been sitting in the top of a closet since 2016.
I know because they came from people that I know, personally. After fixing the coldboot title id, I dumped the MLC of both of them and the data integrity was good.
Both of these were 0103 error systems.