I agree with you. The FAA obviously knows that there are issues with MCAS, since it's been working with Boeing on finalizing a software update that fixes some

I agree with you. The FAA obviously knows that there are issues with MCAS, since it's been working with Boeing on finalizing a software update that fixes some of them for months. Grounding the fleet at least until that software update can be deployed seems prudent the moment there's objective reasoning to suspect MCAS was at play in this crash too. (And I think we might already be there.)