The mesh is fine as far as I can tell, and it got much better when I swapped from Eevee to Cycles. Now there is just a faint line along a couple edges as seen in red here…
Now in blue you can see some stretching of some kind, maybe you can have a look at my nodes and see what you think. I wanted a procedural mold texture I could increase from the bottom of the object, and adjust with a slider to give more or less, depending on preference. It kind of works, but the anomalies above, and the bump isn’t right.
I wanted the image texture bump to increase/decrease with the gradient. To be honest this is the first procedural texture I have created myself from scratch so I’m sure it’s far from perfect.