They will encrypt the heaters' connection to the car. Breaking encryption is a dcma violation. Aftermarket can replace the entire seat but that's very expensive.
Tesla already does this.
https://insideevs.com/news/680181/hackers-jailbreak-tesla-model-3-unlock-free-heated-rear-seats/
If anyone sells what the researchers figured out, they can be sued and jailed just like modchip developers have been.