I have been interested in that-like work and also just recently saw a post somewhere else where a guy claimed that he changed the vid & pid on his new WWAN card for his Lenovo laptop. However I am doubt much about his claim because he only had to simply remove the whitelist from the existing bios on his Lenovo (unlike HP computers) if wanting his new card to work on his Lenovo, and first of all, he did not present any evidence. Also one more thing I think here is that is off-topic here because topics like that would be ones related to PCI devices, not to bios at all...
I read this 1 year old post way different than you, What I think he wants is to do is rewrite the firmware of the PCi device not play around with computer bios settings. Way more difficult and requires the knowledge of how to communicate with chips or IC's firmware that is embedded within in it. nothing to do with BIOS Your example of of WiFi card or USB would translate into making it do things that it was not supposed to do like increase power above what is legal or transmit/receive on unauthorized frequencies or even transmit on DFS (radar) frequencies with impunity