OldFrill
American English has a far greater influence on everyday communication than Latin, so insisting on Latin-based 'corrections' often ignores how language naturally evolves.
Ultimately the majority will follow American English and "media are" will be seen as old fashioned and an indicator of age (probably already is), for now, both are acceptable.
That is probably true, but there is a difference between one medium and several media, so the distinction matters, I think. I'm not one for getting upset about language evolving - nobody talks like Chaucer these days - but where words have different meanings I think it's important to use them to describe the concepts they represent.


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