Admittedly I have not, but I did search for and find similar issues on their github before making this comment, and I do plan to investigate this more one day and possibly make a proper issue. There are indeed a lot of "X tool is broken because of Y" statements of varying credibility floating around in the multimedia community where it's unclear if they were actually ever reported upstream or even double-checked recently (people still claim that VLC uses nearest-neighbour chroma scaling, for example, but that's no longer true (except for screenshots, it's still a problem there)), and that is something I'm trying to work against by investigating and reporting this when I can.
But since I don't use IINA myself and since, as another commenter pointed out, IINA bug reports don't seem to get a lot of responses on average, it hasn't been the highest priority for me.