I've seen it work in reverse when the systems are just "too hard" to change. Think old legacy systems with large monolithic mainframe architectures as an example. Because it costs too much money to change them and the business needs to keep running many restructures just fail and managers just keep dropping.

I see Conway's law as an equals relationship IMHO, not a cause. The side that can give ends up adapting to the side that can't. In newer business where the architecture isn't established of course the structure influences the design. As the architecture matures and is worth a lot of money to replace it sometimes switches the other way. This of course can kill a lot of big corp's and IMO one of the biggest reason they may seem less agile to startup dev's - they have so many use cases to handle and systems have grown so complex it is a lot of effort to understand yet alone modernize these architectures. Often as well because they have been successful for awhile the regulators/governments have caught up with them and they have obligations that aren't so easily depreciated in any replacement.