[labawi]

Yet even MAX didn't have triple redundancy of all sensors, and I don't think it is customary to have triple redundancy for all sensors in pretty much any plane.

Some things are more or less important, and even insignificant for safe landing. Triple redundant sensors won't save you from programming errors, birds or cables in rotors, batteries bursting into flames which is still more likely to cause a crash than your only camera or microphone failing - probably even a GPS failure, as long as you have a working IMU.