You're right my comment was off the cuff but I stand by it's logic. I didn't say Kovid was a terrible person, just not great. Having not done research into him specifically I just noted with the parent that certain qualities such as supposed abrasiveness often overlap with qualities I dislike, like using the Lenna image.
My point is that using the Lenna image is a signal, just as you rightly point out so is my comment. I know exactly what the image is and is used for. But I also think it's sad that it's politically charged to say using a Playboy image in a literally objectifying fashion as a test-subject by a women who's requested we don't use it is bad.
It's not a sudden ban, it's been an issue since ~2015. Fun fact I learnt in this, Goyal is totally open to changing it (https://github.com/kovidgoyal/kitty/issues/661), it's simply no-one changed it. I'll see if I can, thanks for the correct call-out.
Using the 'Lena' image is only a signal for those who want to signal something. For most people it is just the standard graphic to use when presenting image processing software. There has been a movement to ban the image but that movement is most likely not nearly so widespread as some people seem to think it is. It wholly depends on which 'bubble' you are in whether using that image is a deadly sin or just daily routine. I suspect Goyal used it in the latter way, not to send some signal to the Image Inquisition.
> using a Playboy image
In all honesty, until I read about that I couldn't have imagined the original was a playboy image. What is really used and we see online is a cropped portrait of a playboy image. I am not even sure that playboy image may have been pornographic. Nudity != porn. What is sure is that cropped portrait is not in any way pornographic.
So I kind of have difficulties on drawing opinions about that. Surely the model doesn't have any copyright on that photo, rather the photographer/publisher have and apparently nobody has cared. I would not use it today out of empathy given the model would rather not see her image still being used today and how easy it is to replace it. I feel that consent is above copyright laws.
I have mixed feeling about the argument that the presence of that totally non pornographic portrait would make women feel less welcomed in science. On one hand I would say that if they say so, that could be true. On another hand I would ask if these women really are representative of all women? Does it really matters? Should we avoid posting picture of portraits and stick to animals or still life scenes? And if not why should we avoid only women ones?