My experience is that 95+% of businesses will follow GPL obligations, even without teeth. The <5% bad actors are a problem, but that doesn't negate that it mostly works.
My experience is, for businesses who pay attention to open-source licenses, they will avoid GPL libraries like the plague (GPL applications are usually fine, though there's sometimes some skepticism).
But not all businesses pay close attention to open-source licenses.
I have to assume that scale has something to do with it. Huge companies usually take that pretty seriously. Tiny companies... eh, they might not even be aware.
Concur on this about avoidance. From my own experience at a startup years ago, the corporate counsel was pretty much hostile to any GPL libraries being used in the companies product, and was especially hostile to the AGPL, categorically refusing to support use of anything using the latter.
