Now while you have a point. Keep in mind that a ton of people never finish a game and you can spend 40-50h in act one and by all accounts Act 1 is pretty polished because it was the part that you could play during early access. It is possible that the later game might not live up to the first act but the truth is a lot of people will never make it that far.

As a sidenote there is one reviewer that I know that played a lot of the early access that finished the full game in a bit over 50h a couple of days after release and he was very positive about it. (Even the later parts)