Canon has just annouced use of HEIF in ther upcoming EOS 1D Mark III flagship camera. With such a big player in the game adopting this format, I think it is time adobe get on board and add the ability to export photos using HEIF.
It's the EOS-1D X Mark III. The EOS-1D Mark III is a very old camera. Lightroom (cloud) does not offer much choice yet, but in what situation would you prefer to export in HEIC instead of one of the other options that Lightroom Classic offers?