Yes, that's nonsense.
It makes about as much sense as someone telling you that anything you play on a guitar is the copyright of the guitar manufacturer or string manufacturer or the manufacturer of the mike and amp you rigged it up with.
Think of the hundreds of songs in the 80s built around Yamaha DX7 presets, particularly the electric piano.
Whitney Houston's estate would be penniless paying royalties to Yamaha.
However if you repackaged the Arturia presets and attempted to sell them as your own, that would be a different story, because they are Arturia's intellectual property. But any songs you make with them are not.