I’m saddened by the tragic loss of life, and the difficult situation that the crew was given. There is no excuse for the deficiencies of the MCAS design.
That being said, there is no universe in which multiple attempts to engage the autopilot at low altitude with an active stick shaker was the correct choice. There are times in this business in which the only correct choice is to turn off all the magic, grab yourself a handful of aircraft, and return to the basics of pitch, power, and performance. Not knowing the specifics of the crew or their airline, I will leave it to someone else to determine if the crew actions were deficiencies of the individuals or deficiencies of their training, but deficient they were.