[$] The supposed decline of copyleft

At DebConf17, John Sullivan, the executive director of the FSF,gave a talk on the supposed decline of the use ofcopyleft licenses in free-software projects. In his presentation, Sullivanquestioned the notion that permissive licenses, like the BSD or MITlicenses, are gaining ground at the expense of the traditionally dominantcopyleft licenses from the FSF. While there does seem to be a rise inthe use of permissive licenses, in general, there are several possibleexplanations for the phenomenon.