This is a very touchy area indeed, and I think that especially for those people who are not on the "in" about the topic, I would suggest approaching any article about it with reservation and suspend judgement. To do otherwise is to risk committing an injustice through false accusations. Slander and libel are very difficult to retract once spread.
One very common equivocation that occurs involves the word "collaboration". The Slate article is one of the few I've seen that actually touches on it. The prewar Polish government of the Second Republic, which went into exile in London and lasted until the end of the Cold War as the Polish government-in-exile (its last president, Ryszard Kaczorowski, died in the 2010 air disaster in Smolensk), never collaborated with the Nazis or the Soviets. They were the first to report to the Allies what was happening in Poland under Nazi occupation (reports which were dismissed). This absence of state collaboration marks a major difference between the Polish state and many other European states who did, in fact, collaborate.
That's one meaning of "collaboration". When we use phrases like "the Poles collaborated", we are invoking an organized, corporate entity ("the Poles"), but since the Polish state is that organized, corporate entity, it is a false statement. "The Poles" did not collaborate. This is not subject to debate.
The other meaning of "collaboration" concerns individuals. Were there individuals who collaborated? Even without knowing the facts, the banal presumption is generally that in any war, especially one involving an occupied country with tens of millions of citizens living under brutal occupation, and occupied by two savage occupiers, no less, you are bound to find some collaborators, both willing and unwilling (for example, at gun point; note also that the Nazis were exceptionally brutal in Poland even with those who were merely associated with people who aided Jews, like children; see the Ulma family for an example[0]). I don't know of anybody who denies that some Poles collaborated with the Nazis.
We must not equivocate the two meanings of "collaboration". There is a discernible tendency on the part of some, either out of ignorance or malice, to conflate the two and attribute to "the Poles" some kind of quasi-constitutional antisemitic racism. (A recent example, ambassador Israel Katz, quoting Yitzhak Shamir, made the stupid and racist remark that the Poles "suckle anti-Semitism with their mothers’ milk". Perhaps a case of racist projection? Perhaps it was Katz and Shamir who suckled Polonophobic bigotry with mother's milk? Can you picture what would happen if the roles were reversed?)
Now, underneath his equivocation is the matter of scale (how widespread was the collaboration) and the question of Polish antisemitism as such.
With respect to the first, the research can be tendentious or sloppy, involving hastily drawn conclusions unsupported by the evidence. An example is Jan T. Gross' "Neighbors". Some Poles do seem to resist any suggestion that collaboration occurred in Poland, however, I would not overstate this, and much of this comes from a place of fear of exaggeration, of dishonest research, and of the exploitation of this tragedy for political ends (the so-called "Holocaust industry", to borrow Norman Finkelstein's phrase) or the use of such facts to downplay the suffering Poles endured under both Nazi and Soviet occupation, including the later communist occupation, which have not been fully digested or researched (the Soviet-installed postwar communist government was especially keen to suppress anything negative about the Soviets, like the Katyn massacre).
With respect to the second, the accusation of deep-seated Polish antisemitism, this is an extremely unfair accusation. Antisemitism is an animus based on racial antipathy. That is the variety that we see in Nazi Germany. In Poland, early 20th century anti-Jewish sentiment mostly revolved around economic resentments and questions around patriotism and loyalty to the Polish state. While there were certainly assimilated Jews who were Polish patriots, the ambivalence among many living in Poland during a period of high national tension led to the European "Jewish Question", which in Poland was not racial in nature. Zionism was also in the air. Recall also that Poland, for centuries the Paradisus Judaeorum, had just been reconstituted after having been partitioned by three empires 123 years earlier, had just fought a war with a Soviet empire with ambitions to spread west, and was facing the threat of a re-militarizing Germany. Having Jewish ancestry was not at the root of Polish-Jewish tensions.
But what is also problematic is a tacit double standard. Be honest with yourself for a moment. Is it worse to be an antisemite or a Polonophobe? Which group is it worse to hate? You might be embarrassed to admit your own biases out loud. Are we to presume that holding bigoted attitudes toward others is something Jews have never done and never do? No cases of Jewish mothers telling their children not to play with the goyim? Untrue that Jews were vastly over-represented in some of the, shall we say, less flattering organs of the Soviet civil bureaucracy, including the cheka, and the NKVD? What are we to conclude here? That "the Jews" were murderous thugs? That "the Jews" are Soviet collaborators?
Level heads must prevail. Time is needed. Until then, I read such claims with a grain of salt.
[0] https://ipn.gov.pl/en/news/10474,Poles-Who-Rescued-Jews-The-...