I think I'm on safe grounds calling it a walking simulator. The gameplay is limited to walking down a linear path and clicking on things until all combinations are exhausted - western equivalent of a visual novel (but with less branching).
It's a decent game / visual novel on its own, but it has absolutely nothing in common with Lem's Invincible except the name and that one core idea (which by now has become a common science fiction trope anyway - like most of Lem's ideas).
It also pulls a future Cold War scenario out of thin air which (as far as I remember) isn't even remotely mentioned in the book (which is more like a whodunit scifi crime novel which then becomes a tech thriller).
Also the decision to use a retro-future lollipop art style similar to The Jetsons is 'controversial' to say the least.
All in all, interesting and decent game (or rather "interactive graphics novel"), but marketing it as being based on Lem's book when in reality it's something entirely different (not just a book adaption with 'artistic freedom', but something entirely different) is a bit too much IMHO.