Poor show
Au contraire!
I never said that no-one moved to Poland during that 44 year period.
You were the one who remarked that "no-one really wanted to move" as if it were down to individual choice rather than state imposed restrictions.
You obviously need a serious lesson in Polish history because movement in and out of Poland while she was imprisoned behind the Iron Curtain was not akin to being in the Schengen Area today.
That is why I also said that "no-one really could move" but it was due to communist totalitarianism (which you deliberately didn't acknowledge).
And yes few could leave. You gave unsourced numbers that over 250,000 left in the 1950s and another in the 1970s. That's nothing especially when you take into account that Poland's population had grown from 30 million to 39 million during that time.
Now compare that to Polish migration today as well as during the 19th and early 20th century.
Checkmate!