I just heard tonight at my local shop that the F4 ATA can be wildcarded, but "The Society" ATA for the IL can't because of some issue due to the prequisite.

I argued that the prequisite was written as "IL" instead of the previous "F4 team ability" due to the whole Thunderbolts/F4 ATA problem.

Can "The Society" ATA be used by Calculators? (Who most of the calculators are 'Society' member anyway: Copperhead, Capt Cold, Mirror Master.)

I'm not aware of any official clarification that suggests The Society can't be wildcarded. As long as a character with the IL symbol is there to wear the feat and thus possess the ATA, any wildcard can copy it like any other team ability that isn't expressly uncopyable (Outsiders, PowCosmic/Quint)

The Society's prerequisite is the IL symbol for purposes of qualifying for the feat being assigned to the IL character, but the team ability text, like the F4 ATA, is free to be used by Wildcards.

This is correct.

Also note that The Society does not have "Can not be wildcarded" as a clause like Squadron Supreme.

A card/TA will tell you if it can't be used by a WC. If it does not state that, then it does.