Richardson became a professor of international affairs and wrote a few papers on the Palestine refugee situation in the early 1950s. He was no Zionist and he was truly concerned over the plight of refugees of Palestine
To Richardson, as to most of the people at the time who wanted to find solution to the refugee problem, it was obvious that the Arab countries were at fault for no solution and that it was their responsibility to help resettle the Arabs of Palestine in their states. In fact, it would be beneficial to them to integrate this population.
This is how you can tell the difference between people who are pro-Palestinian and those who are just anti-Israel. People who really care about Palestinians would insist that Arab states make them into citizens, especially those that have been "guests" for generations. People who truly care about Palestinians want to end their statelessness and their suffering in camps.
People who are anti-Israel insist on "return,' and are angry when Palestinian Arabs themselves say they want to become citizens in Lebanon, Gulf states or the West. They are the ones who insist on supporting UNRWA to keep the issue alive - and Palestinians in limbo - until a fantasy time when Israel is destroyed. They want to see millions more refugees.
Sometimes you need to look at the past to understand the present.