Flight crew response time to an event is dependent on skills as well as training
Curtain Twitcher some time ago pointed out that crews are used to seeing trim running, so at what point do you say "Whoa, somethings wrong"" and reach for the cut outs? SLF here.
Since the MCAS is there to address shortcomings re handling at low weight and aft CoG, might failure of same not require an emergency checklist advising some do/don't elements. A CoG chart with a caution area shown on the lower right corner where MCAS is a requirement might be informative.