The only major reciprocal licenses, the GPL and LGPL, do not require that the entire codebase be under the GPL/LGPL. It only has to be under a compatible license.
From many software vendors' perspective, this is a difference without much distinction. The salient point to them is, if GPL code sneaks into their codebase then they might be forced to switch to a permissive software license, and that might be very disruptive to their business.
And it does manage to have a chilling effect in some industries. In the one I work in, for example, there is a prevailing culture of outright fear of open source software, including of supposedly "business-compatible" code. The worry is that it's hard to trace the provenance of all code, which makes it difficult to dismiss the possibility that, e.g., ostensibly MIT-licensed code is actually GPL-licensed. The fear is perhaps far too great, but from the decisionmakers' perspective this is a situation where their livelihood is potentially at stake, and many of them would rather pay to develop 100% proprietary software than risk getting infected with open-source cooties.
To say that entire industries are being held back by their fears about the GPL would be closer to what I was getting at.
And not in a way that has anything to do with what Mr. Gurley was claiming. What I'm more worried about is the opportunity to fund innovation that is lost when companies choose to sink resources into reinventing wheels rather than picking open source projects off the shelf.
Actually, they might be forced to stop using the GPL code and pay damages.
The GPL is a copyright license, not an ordinary contract, and there's no provision for specific performance. The court isn't going to issue an order commanding the release of your source code.
From many software vendors' perspective, this is a difference without much distinction. The salient point to them is, if GPL code sneaks into their codebase then they might be forced to switch to a permissive software license, and that might be very disruptive to their business.
And it does manage to have a chilling effect in some industries. In the one I work in, for example, there is a prevailing culture of outright fear of open source software, including of supposedly "business-compatible" code. The worry is that it's hard to trace the provenance of all code, which makes it difficult to dismiss the possibility that, e.g., ostensibly MIT-licensed code is actually GPL-licensed. The fear is perhaps far too great, but from the decisionmakers' perspective this is a situation where their livelihood is potentially at stake, and many of them would rather pay to develop 100% proprietary software than risk getting infected with open-source cooties.