This is the consensus of Historians too. A Two state solution might have been possible decades ago, but the constant land grabbing and division of the OPTs by Israel since 1967 has made it unfeasible.
The settlements represent land-grabbing, and land-grabbing and peace-making don’t go together, it is one or the other. By its actions, if not always in its rhetoric, Israel has opted for land-grabbing and as we speak Israel is expanding settlements. So, Israel has been systematically destroying the basis for a viable Palestinian state and this is the declared objective of the Likud and Netanyahu who used to pretend to accept a two-state solution. In the lead up to the last election, he said there will be no Palestinian state on his watch. The expansion of settlements and the wall mean that there cannot be a viable Palestinian state with territorial contiguity. The most that the Palestinians can hope for is Bantustans, a series of enclaves surrounded by Israeli settlements and Israeli military bases.