Let's assume there are some people using these devices in a way that is not compliant with the local codes, because they haven't met the testing/certification requirements.

Genuine question. Which of these options do we prefer? (Choose any number)

1. Deye proactively bricks all the devices

2. US governments compel Deye to brick the devices

3. Local authorities penalize people using the devices illegally

4. No one does anything

1000% #4. No thought is even required to answer that.

#4.

If something actually burns down, authorities will circulate a bulletin and move to #3.

Anyone using the hardware in an off-grid, mobile, or other situation where the cited regulations don't apply, should sue the crap out of #1 and I will contribute to a gofundme for their legal battering ram.