I think people take it to mean "A good craftsman should be able to make excellent work even with poor tools"

But maybe it means "a good craftsman should have the experience to know not to work with poor tools, and if they do work with poor tools and the outcome is bad, it's their own fault for not finding better tools, not the tools fault for being poor"

As in, don't blame your tools, you're the one who chose them. And you're always free to choose better tools.