HEIC is a much better-compressed format than JPEG that all Androids support; iirc JPEG XL (kinda dead) and Google’s WebP are the only other big-name formats with better photographic compression. Windows was the only major operating system that chose to have consumers separately pay the patent fee, none of which goes to Apple. Since Windows 11 22H2, HEIC images work out-of-the-box.
It’s kinda paradoxical. It’s undersupported simply because people don’t like it because it’s undersupported. At least all browsers can open it well.