Technically concentration camps are not limited to the Nazi regime and are do not nessisarily require actively killing the people inside to fit the definition. The internment of Japanese civilians by the US and Canadian governments in WWII fit the definition of a concentration camp. The North Koreans have political prison camps which also fit the description. The notes of periods stopping in the face of extreme stress an malnutrition have been noted at all of these camps by the doctors who have kept records.

You also made quite the logic leap from someone mentioning menstruation in Concentration camps to assuming they meant a literal camp in Gaza. Gaza isn’t a concentration camp… Though the Israeli government has actively throttled supplies to the citizens of the region (including international relief) who cannot immigrate because the neighbouring countries fear Israeli retaliation so you do have a bunch of people who cannot freely move in increasingly unsanitary conditions without access to medical supplies, clean water or fuel to produce clean water and increasing food insecurity in the region has meant that the conditions are primed for a large number of civilians to die… So there are fairly decent parallels in regards to living conditions but the disqualifying difference being largely based around formalized imprisonment.

Not a concentration camp by strict definition and not an “industrial” killing zone like Auschwitz but Auschwitz was very much not the norm for a concentration camp even the ones under Nazi rule so using that as your rubric of “what is a concentration camp” is inherently flawed. Concentration camps are unethical even when they don’t exist to slowly and steadily liquidate their populations.

The commonality stated here is the function of the body due to disease and malnutrition. Demanding proof of one very specific presentation of genocide out of a wide range of possible presentations of active genocide seems to be very mich missing the point.