It’s kind of a gray area, the whole performing/mechanical rights system was obviously invented before streaming. Radio stations pay for performing rights, so the question arises whether streaming is more like radio broadcast or manufacturing and distributing physical copies (e.g. CDs)? Without further legislation, ultimately only the courts can decide that.
My guess is that ultimately streaming rights will end up as their own category, separate from performance, mechanical or sync rights.
My guess is that ultimately streaming rights will end up as their own category, separate from performance, mechanical or sync rights.