Maybe because there are many different set theories. The one taught in school is not a correct one but grokable for most students. Then you got the Zermeno Frenkel set theory, and you got the Homotopy Type Theory one which can yield or emulate the same results. So in a sense the opening statement is correct. There is no consensus on a single "this is THE one and true correct set theory"
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Maybe because there are many different set theories. The one taught in school is not a correct one but grokable for most students. Then you got the Zermeno Frenkel set theory, and you got the Homotopy Type Theory one which can yield or emulate the same results. So in a sense the opening statement is correct. There is no consensus on a single "this is THE one and true correct set theory"