This kind of texture has its own flaws in some types of geometry, specially when a face coincides with grid structure, causing some artifacts due to floating point calculations…
Also, all answers you got for this, here and in the other thread, will suffer from the same problem (since all answers use more or less the same math).
But apart from that I don’t see any other ‘instability’ with it.
To overcome the zfighting, you can scale the texture a bit, so that all faces fall inside each cell and not at their boundaries (again, this will also work in the other setups you got).
Also, in case of Eevee, you should use the ‘Rendering’ instead of ‘LookDev’, as the later uses low resolution floating point calculations for speed up viewport rendering, and that makes zfighting even more visible.