They say the design of the product, not the components are free, if we're going to be pedantic.

To be fair, yes, the proprietary nature of a particular chip is bad for open source, but on the other hand, the marginal cost of a chip is not zero, like it is for software. There's the chip fabrication costs which only goes down in quantity. That means there's an inherent risk in developing a new chip.

However, if you're that concerned about it, there are open source designs which create free truly random bits, so you are free to choose a design that meets your need.

Additionally, and I'm not positive that they've actually done this, but the chip also has fully open toolchain. While the guts of the chip aren't open source, it's possible for the firmware to be 100% open source without any binary blobs.

Yeah, we don't trust RDRAND but we trust this?