They did say that nothing is set in stone except the 4c is going which is expected anyway as the 4c is old tech (a tbi engine with no power steering & a bonnet that has to be unbolted to top up resevoir bottles), plus it'll be six years old in 2020.
Ralph Gilles is head of design for fiat/Chrysler group in Detroit since 2015. He is known for the 300c, & designing the STR brand for Chevrolet too that's who has apparently has said that an all-new Brera could be on the cards. The cars for the American future market could be a totally different type designed & built their & not for European markets. Lots of car makers sell different cars strictly for the American markets, It is plausible to me anyway.
Talk of the Brera to be the launch car for the US market was said years ago, in 3.2 q4 format & a Q-Tronic box, which I could see why the GM parts was such a good idea at the time as customers could get cars sorted out quick without waiting for parts to arrive from Italy on back-order. As we know they launched back in the US with the 8c instead. I would like to see a new Brera, but who knows where Alfa are heading.