ES5 and ES6 are not considered as pure javascript?

Question

Hello friends again😉
Just started the JQuery course and there is a question where they order that a code statement be written in pure javascript, one of the blank spaces where a variable is declared accepts only the value 'var' and not 'let', from there the generated question and several colleagues say that 'let' is not pure javascript ...
Is this true or not?🤔

Answer 1

The reason it only accepts var is because it was written before ES6. ES6 is pure.