Wrong to use "less equal" in a sentence?

As an adjective, equal is defined (to quote one source) as:

-the same in amount, number, or size

-someone or something that has the same importance as someone or something else and deserves the same treatment

-the same in amount, number, or size

Cambridge

From this point of view it is therefore impossible to make a comparative. Either two things are equal or they are not. There is no degree of equality.

Interestingly the same constraint does not apply to unequal. There is an implied degree of inequality in the example of "10 and 2 are more unequal than 5 and 7", and the inequalities may be compared according to the degree of difference.

Hence we may say that things are more unequal, as in your question, but it is loose usage to say they are less equal.

PostScript

I add that this sort of "abuse" (see below) of equal crops up in George Orwell's Animal Farm, which encouraged in a humorous way this distorted usage of the meaning.

This phrase has been used by George Orwell in his phenomenal novel Animal Farm. This is, in fact, one of the seven commandments for the Animal Farm pigs reinterpreted to be read as “ALL ANIMALS ARE EQUAL / BUT SOME ANIMALS ARE MORE EQUAL THAN OTHERS.” This phrase is an ultimate example of the systematic abuse of language and logic of pigs, with the intention to take control of the underlings.

Literary Devices