1. in US you can get a driver's license if you're deaf so as a society we think you can drive without hearing

2. since this is in context of Tesla: tesla cars do have microphones and FSD does use it for responding to sirens etc.

(1) is true, but actually driving is definitely harder without hearing or with diminished hearing. And Several US states, including CA, prohibit inhibiting hearing while driving, e.g., by wearing a headset, earbuds, or earplugs.