“I think Free Software gained momentum **only** because it is non-discriminatory
as far as use of the software is concerned.”

This is deliciously naive.

Free Software only gained momentum because it was supported by Capital. Because Software is a common input to production, and thus having a common stock of it benefits Capital interests broadly in the same way that having standardized nuts and bolts does.

However, not all informational assets are such productive inputs, certainly in most cases artistic works like Films, Videos and Music are not, and so Capital will not support Copyleft music. Therefore producers of these sorts of Intellectual works need a different approach.

Also, even in the case of Free Software, the real financial beneficiaries are not the developers of the software, but the Capitalized firms that use it in production.

Much of this is covered in my essay “Copyfarleft, Copyjustright and the Iron Law of Copyright Earnings.”

http://www.telekommunisten.net/CopyjustrightCopyfarleft

Portuguese and German translations, as well as related information can be found here:

http://www.telekommunisten.net/venture-communism

“In Oekonux we say that Free Software – and other Free Projects – are stronger in terms
of productivity / quality than the capitalist way of production.

Again, this is a fantasy, most developers of significant Free Software projects are employed directly or indirectly by Capitalized firms who employ the software in production, and would not be able to undertake such development without the pay cheque they receive for this.

“That is Free Projects attack the very stronghold of capitalism.”

This is false, Copyleft is in no way incompatible with Capitalism or modes of production based on the theft of surplus value.