I haven't seen that talk, but from a previous one, Flang is closely related to the PGI compiler, and F18 is to escape that.

I wouldn't miss the grief associated with ifort, which doesn't live up to the mythology. The salient feature of the PGI compiler is probably the offloading, and I assume that's Nvidia-specific, but I don't know how it compares with current, and upcoming, GCC support. The research computing world would be a better place if the money spent on proprietary compilers sponsored GCC improvements instead.