Your network card sends your brain to Israel

But they are. As well as open source sound cards and other cards.
No evidence to suggest such a thing.

Please point me to FSF-approved network equipment.

i use ath9k, it has literally 0 firmware and literally 100% open source drivers

It has firmware, you just don't need to upload it on every power up from the host. Don't fall into stallmanisms -because I don't see it, it means it isn't there-.

Yeah nah. That's a strawman.

How is it a strawman? Having binary blobs on your system that you have to upload to the device isn't any worse for security than the device having blobs on its internal flash memory. If anything it's worse, because it means it's harder to reverse engineer the firmware, since you have to somehow get it out of the device first or find a copy on the Internet.

It’s trivially easy to detect that kind of activity. If it was happening it would have been discovered by now by someone like user with the openbsd router. OP makes it seem like a network card could make clandestine links without anyone noticing but OP doesn’t know computers too well.

There is another side to this...
If device firmware can be updated easily (not needing a PIC or AVR programmer or whatever directly connected to it), then that opens the possibility of injecting malicious firmware into the system, for rootkits to bury themselves deep. Kaspersky found such rootkit on some HDD controller firmware like 5 years ago.
But if firmware isn't writable easily, then it's almost like having the code in ROM, so it can't be used for such subversions.

Primarily because
* I use open drivers that I've audited, so if there was a backdoor of any sort, it would have to be entirely in the driver.
* it's trivially easy to detect this kind of suspicious traffic (and I do audit my network traffic)
* everything communicates through SSL so nothing reaches the network card until it's already encrypted and signed, so even if my network card was backdoor'd, it can't MITM me to get my encryption password or keystrokes in the first place.

Tinfoil hatters are the worst because they almost all tend to be horribly ignorant to any and all technical details.

It took like 5 seconds
fsf.org/resources/hw/endorsement/respects-your-freedom