Poland is in the Schengen Area. Cyprus is divided since Turkish invasion, so it is somewhat a special case. Other countries joined the EU relatively recently. However, all four countries are
legally
obliged to join the Schengen Area, they just have to fulfil certain requirements. Without going into all details.. don't you think it kind of makes sense? If you want to join an area without border controls, then for example you should first harmonise the rules on how you secure the external border, immigration control, customs control, etc. It is not as simple as you think.
I do not think it is hyprocritial to require new EU member states to go through certain transition period. A bunch of other European countries went through that process too. At different speeds, but they made it. We are talking about contries; it's not the same as joining your local tennis club, it's a longer and more complex process. If there is anything to blame, then perhaps its your own government which is lagging behind on the necessary reforms. And meanwhile, EU is trying to make it easier for you to travel to the US. So, what are you complaining about?