No need for threats, please.
I have been watching the development of HEIF for some time now and I personally like the format. It is a container format and can be used for a single still image, with or without thumbnail, bursts of images, animations, etc. and supports depth maps and even alpha information. It easily stores EXIF and XMP metadata.
Here are the difficulties:
1) No OS support for HEIF on Windows.
2) No macOS support on versions of macOS prior to macOS 10.13.
3) The only reference standard library (Nokia's HEIF library) only allows non-commercial use.
4) Unless we can obtain an inexpensive license to a HEIF library then we would have to write our own, which we don't have the time or resources to do.
I have contacted Nokia about obtaining a commercial license and hopefully it is possible to obtain one at a minimal cost. We won't license if it has a per-copy royalty requirement.
I expect that in time Nokia's implementation won't be the only available implementation and we will be able to find one that meets our needs both performance-wise and license-wise.
We understand that supporting new formats are important to our customers, but we only have so much time and resources available to us.
-Kirk
P.S. No need for more "I also want this format in PM" posts. It is in our interests to support image formats that our users need to use.
