I'm copying and pasting this comment:

Hi! I’m Jamey Stegmaier, the designer and publisher of Scythe, which features the art and worldbuilding of Jakub Rozalski. I thought I would share my personal perspective here and on the other threads on this topic.

First, I applaud participants of these conversations for looking out for artists. It’s awesome that you’re looking for credit to be given where credit is due, especially to photographers.

Second, if I commission an artist to paint me a picture of a pig, I sure hope they look at photos of pigs while painting them. Artists have been using models for centuries. That said, if a specific element of a specific photo is used as reference for the illustration, credit should be given to the photographer.

Third, Jakub addressed questions about image references 2 years ago on BoardGameGeek: “I used some references, my own photos, and photos from the internet, in several (maybe 10, maybe more), I simply track photo in 1:1, for some elements like: horses or pigs, cow, or specific parts, even some characters.” This is pretty transparent—there doesn’t appear to be any big cover-up or conspiracy.

Fourth, part of the assertation seems to be that Jakub is a hack because he “traced” some animals and people. “Traced” is a bit of a misnomer—if you asked me to trace a photo of a tiger, it wouldn’t look anything close to Jakub’s illustration. I believe Jakub when he says he painted these animals and people while referencing the photographs (not by digitally painting over them). I would point to Jakub’s canvas paintings as evidence that his talents do not require photobashing.

Fifth, perhaps the most troubling accusation was that Jakub created “fake tutorials” (step-by-step in progress illustrations) to make it seem like those illustrations came from his imagination instead of reference photos/images. This is troubling to me because it’s stated as fact, yet no evidence of it is provided. The closest is an image from artist John Park that depicts a sideview of a mech, but the mech is very different from the one in Jakub’s step-by-step illustration.

I’ll end where I began: I believe in giving credit where credit is due. Today I’ve e-mailed with Jakub about crediting any photographers from images where he used a specific animal or person as reference, and he’s going to do his best to find them (this is like me telling you to replicate a specific Google Image search from 4 years ago—it isn’t easy). In turn, I hope you will keep an open mind about giving Jakub credit as well. This is a two-way street. To completely discredit his illustrations—each of which is a complex amalgamation of different elements in the foreground, midground, and background—just because he used some reference photos for some animals and people doesn’t seem fair.