The dev literally asked for honest feedback in the OP of the thread. Do you believe that only honest POSITIVE feedback should be given? I'm generally a fan of the dev's work (although I tend to agree that starting another project while having three unfinished projects that are lucky to get 2 minutes worth of content every three months already isn't exactly a good look), but I also don't think that if a dev asks for honest feedback, that people should be expected to just "not play it and move on" or "just move on if they don't like it". They arrived at the thread that asked for their feedback, so they gave their feedback.
So you getting on everyone's ass for giving feedback after being asked for it isn't really constructive either. It's one thing if someone comes in and their only feedback is that they don't like futa/trans full stop. Then just tell them to blacklist the tag so they stop seeing it.
But if someone is giving feedback that is actually relevant to this game or this dev, like pointing out that starting a bunch of games and not finishing any isn't a good look, or reusing the same models over and over, or using a young male/shota protagonist every time, or just being not a fan of having the son be adopted rather than blood related (despite only being on subscribestar rather than patreon), and other similar pieces of feedback, there's no reason to for that feedback to be greeted with hostility.