Well, John. That may be true or not. According to the CD Baby article and the others I've linked to, the PRO's does not collect for self-published music released as downloads only.

Be aware the two premises 1) this only applies for self-published works that 2) only are available for download.

The PRO's does of course collect for everything else.

This is why songwriters also can collect monies from SoundExchange, Tune Core ect.