Because there was never plan to create a Palestinian state. It was all a lie...
There was a plan. That way they would have all the Palestinians in one place so that they could be exterminated. But the Palestinians have been spread across Jordan and other countries in that region. Palestinians are not only muslim though. And as we have seen from the situation in Syria, few muslim countries feel sorry enough for their own relisgiously linked brothers and sisters to want to help them.
Now is Netanyahoo who wants to send the Palestinian running for refuge to Europe
The Israelis have always had a policy of making life miserable for Palestinians sufficiently so they leave on their own volition. They even have a name for the strategy that slipped my mind at the moment. It has not work and will not work.
What I find interesting is that 70 years after, the Muslims in Europe largely outnumber the Israelis.