I can't say exactly how much it take to develop a game like that, but let's look at it his way:
- The game doesn't have any complex mechanics, this is a point and click game, and the game engine is already there.
- The story is linear, and have few branches at best.
- The writing is trash.
- Few short animations.
- The dev has spent around two years working on the same game, if he is any good at coding/conception, it should be extremely easy to push new updates by now, just a matter of copy pasting text and renders into the right place.
- The only thing that can take take is rendering, but we see other devs doing it much faster.
I am a developer my self, but never worked on game programming. i don't think however developing point and click games is really "game programming", and i am pretty sure there is little complexity involved, for the most part it is just an interactive comic book, and i see publishers like Y3DF releasing sometimes twice a month.
I say with a budget as of ICTOR, if you are not releasing twice a month(you can hire a small team to help with rendering), you are just being lazy, once a month is acceptable. but more than that is just milking it.