okay well maybe it does take place in the modern era, I just zoomed in on a newspaper and it has "www.journal.fr" written on it, also Colette's bike looks pretty recent

The old TV at the beginning can be justified by it being an old lady's house and maybe by stretching a little bit, the old TV and fridge in Linguini's house is because he lives in a small, cramped and cheap apartment because he's poor?

But even considering that Pixar really fantasized Paris in this movie