Anyway the point was that taxing receivers would be an option if they had wanted to finance the system, but for some reason they didn't, not so much to discuss this data storage tax to be paid out to the music industry
The tax is based on a quirk of copyright law designed by the media industry all the way back in the age of cassette recorders. Music companies realized that people were making copies of their songs from the radio for free (you could put together entire albums if you timed it correctly!) and from the cassettes they bought, and after some mess the "thuiskopie" (home copy) system was born.
Basically, you can make legal copies of any media you have legal access to as long as you pay the fee. This fee goes directly to on organisation (think MPAA but for all artists) which then redistributes the money according to Some Kind Of Model[1]. The fee is part of the sale of any digital or analogue container that can contain copyrighted works; it's a fixed price fee (https://www.thuiskopie.nl/nl/opgave/tarieven). Professionals who won't use their devices to store other people's work can get their money back if they fill in a form and send over the right paperwork, but let's be honest, nobody does this.
For a long time, the de facto interpretation of the thuiskopie law was that a copy you make for yourself (or your direct family/friends) at home is legal. That implied downloading MP3s and other files from the web was also legal [2]. Torrents involve sharing, so they were always off the table, but copies of torrented files given to family was treated like a legal copy. You could still be caught for piracy, but as long as someone else got you all of your pirated disks you were pretty much Technically Okay.
This interpretation was killed off when the media industry won a lawsuit against the government. It was always too good to be true, but it seemed to be one of the ways many pirates were appeased about this law. I'm pretty sure everyone considers this system to be stupid now that it's no longer a de facto piracy license. The copyright lobby is incredibly strong, though, so I doubt we'll see a change any time soon.
The copyright industry gets to charge you twice for the media you listen to. As long as this stupid system remains part of the law, I'm personally opposed to any subsidies for commercial media. If only a politician worth voting for actually cared about this crap...
[1]: Yes, this is legal, though I still don't know why.
[2]: Software has always been excluded from this, though; downloading software and games was never part of the deal, and software companies can't claim their take from the Thuiskopie system
I would think the fairest tax rate would be such that giving people the ability to easily copy music would be profit-neutral for music owners/producers.
If so, tax revenues would only have to cover whatever that decreases the profits of music sales by, and that isn’t necessarily 100%.
(Of course, determining lost profits basically is impossible, even ignoring that the ideal solution would determine that for each rights owner in isolation, but that is a different issue. Certainly, requiring all digital music to be free doesn’t avoid that)