I wasn't knocking OSX. Their system is awesome. The OpenGL specification for every Mac is published on line and they stick to it. Their conformance to specifications is what makes them seem so hard headed some times. If it's not in the spec, they don't do it. On the other hand, if its IN the spec, it works.
I suspect something changed with the shader compiler, possibly in the Qt code. Previously, it didn't care if my shader used more texture units than OpenGL said it supports. It worked with 32 textures anyway, on my Mac before this update.
However, the fact that it worked is only happenstance. There could be other bad side effects, like broken textures, or broken shaders, or unseen other corruption. It might work on one Mac but not on another slightly different model.
The spec shows that all current models of Macs support 16 concurrent texture units. I will make SoH work with only 16 textures. That is my project for today.