If you want to watch the SB, but not have it count in the ratings find a live stream on YouTube and just watch that.
If you’re not a Nielson family it doesn’t count.
"Official" NFL live streams (Yahoo/Verizon, Twitter, etc.) are counted in ratings...use one from some person taking a video of their TV screen and streaming it. (Any YouTube streams might get shut down mid-stream due to the NFL copyright police tho....use an "alternate" stream provider).
The real pain for the NFL will come when the major TV networks renew their contracts in the 2020-21 timeframe...hundreds of millions in "discounts" to be had due to lower ratings.