This one might be a controversial opinion with regard to writing, but I feel it needs to be said. A definition of ‘contemporary’ is: “belonging to or occurring in the present.” While you can sprinkle your world with vague references, directly talking about a piece of pop culture is perfectly fine. I will use song names in some of my works, for example (not lyrics, that can lead to copyright issues). This is especially useful for popular songs that will remain classics for decades.
Some folks think it ‘cheapens’ the work, which is a valid opinion, but not one that I share. I mention video games in my stories, for example, simply because that’s in the characters’ interests. I don’t see a problem with it if it’s relevant to both the time period and location. Many writers of the past, including Shakespeare, did just that. The value of writing in the present is to be in the present.
Obviously you don’t want to crowd your book with brand names here, there, and everywhere. Have a reason for the product to be mentioned. It can be something as simple as ‘well, the character likes it’. Not everything has to have some deep meaning. The color of the carpet isn’t going to lead to the meaning of life, for example. At least not for writers who don’t utterly oversaturate their works with symbolism (and by that, I mean going into extreme excess).
Your readers will be mixed on this, as will writers, as will editors. I’ve been scolded by editors before for including pop culture references, but it’s honestly up to preference. When I’m reading, I don’t mind seeing it, as it gives me a basis for time and place. If the world is heavily affected, it also brings a sense of normalcy to some areas that might not be as impacted as others.
It’s all up to you if you bring the present into the present, with moderation, of course. But as someone who both reads and writes a lot of urban fantasy, I don’t mind the references. Either making up similar names for brands or using the brands themselves (if your world is just an alternative Earth) is perfectly reasonable.
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